Study On Design And Mechanism Analysis Of Main Parts Of Plot Seeder

The mechanization level of plot breeding is lower at present in China, and the current plot seeders have their shortcomings, such as pretty in price, complicated structure, high error and low efficiency of drive mechanism, inconvenient adjustment and poor adaptability, so these machines don’t adapt to develop of plot breeding in China. In order to better realize mechanization of plot breeding on rape, the plot seeder has been invented and developed according to mechatronics realized by electronic control and motor drive on the basis of (?)yjord metering principle (invention patent number:201010247796.2).After theoretically analyzing and determining for several design plans in this dissertation, the configurable schemes of design, system and control requirements of key parts are ascertained firstly. By Pro/Engeering software the model of plot seeder is established and the total drawings from the solid modeling are completed. By Autocad software the total drawings of plot seeder are further improved. According to the design requirement, the plot seeder is made.On that basis, analysis on mechanism of key devices, study of control system, test analysis and parameter optimization analysis of key devices and so on are held chiefly. The main research contents are as follows:1. Method of supplying seed by step of electromagnetic force is proposed.According to the characteristics of supplying seed, the automatic system for supplying seed for plot seeder driving by electromagnetic device is developed. The structure and work principle of total system are analyzed. The structure parameters of parts are ensured and dynamics analysis is held.The motions about disc for supplying seed, transmission mechanism and drive device are analyzed. According to work requirements, control circuits designed by C language control work time and time interval in which electromagnetic devices drive device for storing seed and device for supplying seed for realizing accurately filling seed and supplying seed. By the performance test of the automatic system for supplying seed for plot seeder, the results show that uniformity and reliability of supplying seed is high. By load test, the results show load change has almost the same regulation and stability is high. The automatic system for supplying seed may continuously supply seed for 34 plots, which has broken throw the traditional artificial mode for supplying seed for plot seeder.2. The system for storing seed is developed by electromagnetic force drive, which may be in coordination with device for supplying seed. The structure and work principle of the storing system are analyzed. The structure parameters of parts are ensured and dynamics analysis is held by electromagnetic force. Structure parameters and work parameters are ensured as test object by analysis of work performance. The regression mathematical models are created between test factors and performance parameters of device for storing seed. The optimized combination of structure and motion parameters is found by DPS software and matlab software. The storing system controls by work button, which takes the place of the traditional artificial mode for filling seed.3. Mode of combining electric control with stepping motor driver is proposed. The metering system driving by stepping motor controlled by electronic pulse from magnetoelectric transducer is developed. The structure and work principle of device for filling seed and device for transporting seed are analyzed and ensured structure parameters of key parts for rape. Motion of rape seed in the process of filling seed is analyzed by high speed photography and dynamics analysis is held. According to work requirements, control circuits designed by C language control rotation velocity of stepping motor is in coordination with movement speed of plot seeder on different length of plot. The analysis of the factors influencing work performance in the processes of filling seed and transporting seed is held and the regression mathematical models are created between test factors and performance parameters of device for filling seed and device for transporting seed. The optimized combination of structure and motion parameters is found by DPS software and matlab software. The metering system has broken throw the traditional mode of mechanical drive for metering and successfully realized steplessly adjust rotation velocity of metering system driving by stepping motor according to different plot length and different movement speed of plot seeder.4. Mode of flexible and centrifugal on the plan for distributing seed is proposed. The system for distributing seed driving by DC machine is developed. According to the work principle of distribution device for rape seed, the flexible and centrifugal device for distributing seed with symmetrical double edges is designed. Structure parameters are ensured and work principle and dynamics of the distributing system are analyzed. Influences of different rotation speed of the flexible and centrifugal device for distributing seed with symmetrical double edges, centrifugal device for distributing seed with symmetrical double edges and unsymmetrical device for distributing seed on the CV of distribution uniformity are analyzed by univariate analyses. The results show that newly designed device for distributing seed is best among three devices for distributing seed when rotation speed of distribution device is 800～1400r/min, while the best rotation speed is gotten when seeding rate for rape seed is 5g/plot. The system for distributing seed may choice different rotation speed for distributing seed by rotation switch according to different seeding rate for rape seed to improve the adaptability for different plot length and different seeding rate.5. According to the mechanics analysis of opener of plot seeder, the mechanics is test at the different double-edge angles by analysis of vibration signal software. Analysis of the change regularity of openers’load when the key devices is at the best. By the performance test, eligibility rate of sowing depth is ensured.6. The performance test of plot seeder is held. Three technical indexes (the CV of seeding rate stability, the CV of seeding uniformity, the CV of seeding consistency between the lines) are test. The result shows of shows three technical indexes are fit the technical requirements.The testing result of Testing and Appraisal Station on Agricultural Machinery of ShanDong is that testing indexes of plot seeder achieve the requirement of enterprise standard. The identification result of Ministry of Agriculture is that the plot seeder has reached the international advanced level.