Design And Research On Automatic Adjusting Seed Cotton Cleaning Machine

Cotton,as a traditional cash crop in China,has the dual properties of agricultural product and strategic material,which puts forward higher quality requirements for cotton processing.Due to the differences in seed cotton varieties,planting areas and harvesting methods,the seed cotton material properties are quite different,which made the cleaning efficiency of seed cotton cleaning equipment unstable.In order to adapt to the different material properties of the seed cotton to be processed and improve the cleaning efficiency,a seed cotton cleaning machine with automatic adjustment function was designed in this study.The main research contents are shown as following:(1)By analyzing the material properties of the seed cotton and the influence of the working parameters of the seed cotton cleaning machine on the cleaning efficiency,the automatic adjustment parameters were determined as the speed of the spiked cylinders and the space between the spiked cylinders and the grid bars cells.Through comparative analysis,the overall design scheme was determined.(2)According to the overall design scheme,the key components of the self-adjusting seed cotton cleaning machine were designed.First,the theoretical verification of the lead screw and worm gear of the spacing adjustment mechanism was carried out.The results showed that the stability and self-locking of the lead screw and the contact fatigue strength of the worm gear tooth surface could meet the design requirements.The designed spacing adjustment mechanism was simulated by ADAMS.The results showed that the SWL U-type worm gear elevator could meet the lifting requirements of the movable grid bars cells.Then,the structural design of the movable grid bars cells and the chassis was conducted,and the support chassis of the movable grid bars cells and the frame of the lower level cleaning chamber were analyzed by ANSYS.The results showed that,the maximum equivalent stress of the movable grid bars cells support chassis was 18.93 MPa,and the maximum deformation was 0.85 mm.The maximum equivalent stress of the chassis was 48.21 MPa and the maximum deformation was 1.37 mm.Finally,the design and selection of the sealing structure,the guide device,and the drive motor of the spacing adjustment mechanism performed.(3)According to the design requirements of the control system scheme,the hardware of the control system was selected,and the hardware wiring diagram and electrical schematic diagram were drawn.Based on the PLC,the trapezoidal program to control the position of the movable grid bars cells and the speed of the spiked cylinders was then written in GX Works2.And GX Simulator was used to simulate and test the program.Finally,according to the registers and soft components set up in the control program,the touch screen interface of the machine was designed through the Utility Manager.(4)The trajectories of seed cotton and impurities were simulated by EDEM,and it was determined that the seed cotton and impurities could be separated under the action of the spiked cylinders and the grid bars cells.A test device was built and the full factorial experimental design method was used to conduct the test.The test data was analyzed with the cleaning efficiency as the evaluation index,and the optimal combination parameters when the cleaning efficiency reached the highest were determined as follows: the speed of the spiked cylinders was 660 r/min,and the space between the spiked cylinders and the grid bars cells was 16 mm.Compared with the combined parameters before optimization,the cleaning efficiency growth rate reached 17.1%.Finally,the analysis of variance method was used to analyzed the test data.The results showed that the influence of the spiked cylinders speed(P=0.003)and the space between the spiked cylinders and the grid bars cells(P=0.038)on the cleaning efficiency had the statistical significant.The primary and secondary order of the influence degree of these two working parameters on the cleaning efficiency were:the speed of the spiked cylinders > the space between the spiked cylinders and the grid bars cells.