Finite Element Modal Analysis And Optimization Of 4SY-1.8 Rape Windrower Frame

Traditional manual harvesting has the following disadvantages: large labor intensity,high production costs, low efficiency. At the present stage,mechanical harvesting of rape is divided into combine harvester and segment harvest. Based on the high lose rate of rapeseed with different mature degree by the combine harvester and its long period of harvest, the overall harvest costs is higher, which restrict the promotion of combine harvester technology in large area in the actual production. The study of rape windrower is a pressing matter of the moment, whichis suitable for our country planting pattern with stable working performance.The frame of 4SY- 1.8 rape windrower is the base and bear the load of whole assembly. The pros and cons of the frame design play a decisive role on comfort, security, stability and working reliability of the windrower machine manipulation.Based on the analysis of current situation on finite element analysis for rape windrower and domestic agricultural machinery at home and abroad, new 4SY- 1.8 rape windrower frame with stable working performance was made out by improvement design. The frequency range and the amplitude of excitation force of each component were analyzed in detail; three-dimensional model of 4SY-1.8 type rape windrower frame was constructed, finite element modal analysis was carried out to determine the natural frequency and vibration characteristics of windrower frame; the rationality of modal simulation analysis was tested by hammering method and the control strategy of vibration amplitude was proposed; the functional relationship between cutter drive shaft torque, cutter shaft rotational speed, the first-order total deformation values of modal analysis and each test point average peak vibration displacement was fitted by RBF neural network; finally the windrower frame was improved and field harvest experiment was carried out. The main research contents of this paper are as follows:(1) The exciting force characteristics were analyzed which effected the vibration amplitude of frame in the operation process. The working principle of 4SY-1.8 rape windrower was analyzed in brief, the effect rules of key components structure and operation parameters on the exciting force were determined and the frequency range and the amplitude of excitation force of each component were mainly analyzed. Three-dimensional model of 4SY-1.8 type rape windrower was constructed to carry out the kinematics analysis by using the Pro/E software. the difference and common law of acceleration change was elaborated in cutter driving system for each test point.(2) Based on the structure of the self-made4SY-1.8 type rape windrower, finite element modal analysis of e windrower frame was carried out. In order to reduce the frame vibration, installation of transverse and longitudinal stiffeners was put forward. The natural frequencies and vibration characteristics of windrower frame were determined by finite element modal analysis.(3) The rationality of frame modal analysis was verified and the strategy to control vibration amplitude was proposed. The error between the results of the simulation analysis is small. After installation of the transverse and longitudinal strengthen stiffeners, the first order natural frequency of frame was raised from 9.761 Hz to 10.779 Hz and 10.447 Hz respectively, which avoid the inertia vibration force frequency 8.217 Hz of knife reciprocating. The test results of frame vibration displacement showed that the vibration displacement peak to peak value of frame test point is reduced by an average of 16.09% when installing transverse stiffeners than that of installing the longitudinal stiffeners.(4) The vibration characteristics of 4SY-1.8 type rape windrower frame was carried out. By measuring the pressure and flow of cutter hydraulic driving system, the change regularity of cutter drive shaft torque and power consumption was analyzed. The functional relationship between cutter drive shaft torque,cutter shaft rotational speed,the first-order total deformation values of modal analysis and each test point average peak vibration displacement was fitted by RBF neural network. Neurons weights of each layer were obtained and the correctness of the RBF neural network model was tested.(5) The power spectrum characteristics of windrower frame test point after improvement was obtained and regularity of the similarities and differences were analyzed. The field stability test was carried out aiming at the improved windrower frame.