Structure Design And Research Of The Compressing Mechanism Of The Big Baling Machine

The grass industry in china has good development prospects.However,in recent years,the problem on lack of production capacity with grass product have become more obvious.Development and Application of large rectangular baler is one of the effective means to solve this problem.the working principle of compressing mechanism with single and double piston was studied.The mathematical model for calculating the crank torque of compressing mechanism was established.Comparison and experimental verification of crank torque of compressing mechanism with single piston and double piston was carried out by using this mathematical model.Under the same baling density,the conlusion that power matching of compressing mechanism with double piston is smaller than that of compressing mechanism with single piston was pointed out.According to design requirements,the compressing mechanism with double-piston was designed,and the parameterized design scheme of the compressing mechanism of large rectangular baler was proposed.Main contents of the study are:After the mathematical model of crank torque was established and solved,The author come to the conclusion that during the compression process which the forage density form 0 to 20,under open compression conditions,the peak torque of the double piston decreased by 21% compared to the single piston.Under closed compression conditions,the peak torque of the double piston is decreased by 9.27% compared to the single piston.Therefore,the compressing mechanism with double piston needs less power in the process of compressing forage.Double-piston compression tests were conducted with grass at moisture content of 15% by using compressing mechanism test bench,and the mathematical model was modified based on the experimental results.the effect of friction on the peak crank torque was considered,and the requirements of calculating the peak crank torque of the double piston compressing mechanism was satisfied.The correctness of the mathematical model was verified.According to the design requirements for bales with a density of 250 and a section size of 1.2m and 0.9m,the structure of the double piston compressing mechanism is designed,and the design parameters such as piston thrust s=750 mm,crank r=374 mm,upper and lower connecting rod L=1165mm,and matching power of 189 horsepower were obtained.the virtual prototype was established by using solid works software.According to the series design scheme proposed in this paper,The double-piston compressing mechanism of a large rectangular baler with a baling density of 300 was designed.and the design parameters such as piston stroke s=900 mm,crank r=449 mm,upper and lower connecting rod L=1290mm,and matching power of 316 horsepower were obtained.The results of the research and analysis above show that the design of the double piston compressing mechanism of the baler has important engineering practical significance for the development of the baler.