| Rape is the important oil crops in china,and combined harvest for rape has advantages of convenient and efficient compared with reaped by hand.Traditional rape combine harvester have many moving parts and with a long mechanical power transmission line,considering the remaining problems,a set of hydraulic drive system with series-parallel combined double pumps and motors was designed,and the system was applied in 4LYZ-1.8 rape combine harvester.In this essay,based on the test platform which are made by machine and related test equipment,the load of power and speed analysis of hydraulic circuit of rape combine under no-load and load condition were studied,as well as simulation analysis of hydraulic system and its components were developed.This paper was intended to simplify the structure of rape combine transmission and offer a scientific basis for effective matching and power distribution of rape combine harvester.The main research contents and results are as follows:(1)Hydraulic drive system with series-parallel combined double pumps and motors was designed.Based on the study of load,speed and other performance analysis of rape combine harvester moving parts,project design of hydraulic system,parameter calculation and hydraulic components selection were developed,and the rotating speed of critical components,power range and working principle for hydraulic drive system were determined,as well as the design of the core components.(2)The relation curve between the circuit of the motor speed and the open angle of throttle was determined,and the result shows: The rotate speed of circuits enhanced with the throttle opening angle increased;motors with the same displacement and in the same circuit had the same value;the values between motors which had different speed and in the same circuit had large difference with the change of the throttle opening angle.It was kwon from the experiment of engine speed affected on the ?~n curve that when the engine speed was between 1000r/min and 1800r/min and the throttle with the same opening angle,the poor of the maximum and the minimum of the header compositor,forced feeding roller,cylinder speed and throwing machine were 21.4r/min,49r/min,50r/min and 42r/min,respectively.(3)The influencing rule of the main working parts speed for the hydraulic circuit on the total power in load sensitive system,the results of orthogonal test analysis showedthat the primary and secondary order of the influence on the total power of rape combine harvester load sensitive systems was cylinder speed,throwing machine speed,the speed of header compositor and feeding roller speed.According to variance analysis of orthogonal tests,power consumption of load sensitive system is sensitive to the speed of threshing cylinder very significantly,while the speed of cyclone separation tube inlet and the speed of header had significant effects on the power consumption.(4)Power consumption testing and analysis of the circuits with main working parts were developed.Based on the experiments of power consumption analysis for hydraulic circuit,the average power consumptions of five parts had been concerned when the average feed rate was 1.5 kg/s,the five parts included header,forcible feed rotor,threshing cylinder,throwing machine(conveying appliance was also belonged)and fan,and the results showed the average power consumptions were 1.68 kW,1.00 kW,5.11 kW2.28 kW and 1.80 kW,respectively.(5)The effect of different key components speeds on the material quality distribution characteristics for rape combine harvester outlets was carried out.Tests showed that:(1)the primary and secondary order of the effect on longitudinal axial flow threshing and separation installation row grass mouth materials was threshing cylinder speed,header speed and the speed of fan;(2)the primary and secondary order of the influence on mass ratio of outlets for cyclone cylinder was the speed of fan,composite conveyor speed and threshing cylinder speed;(3)the primary and secondary order of the effect on the mass ratio of outlets for fan was the speed of fan,threshing cylinder speed and composite conveyor speed.(6)Simulations for selected hydraulic components were contracted according to software AMESim,the simulation models of hydraulic drive system with series-parallel combined double pumps and motors were developed,and compared the simulation value to the testing value for load sensitive system.The simulation results showed that the power of circuit 1,circuit 2,circuit 3 and circuit 4 accounted for14%,9%,44% and 20%,respectively of the total power consumption of load sensitive system.(7)what was more,the field experiments of hydraulic drive system with series-parallel combined double pumps and motors which was applied in 4LYZ-1.8 rape combine harvester were developed to tested its performance and reliability.It turned out that the rape combine harvester working smoothly,the hydraulic drive system could satisfy the demands of rape combine operation and worked stabled,and realize stepless speed regulation as well as change the height of the header and the reel to adopt differentoperation conditions,load sensitive system could give the pressure and flow rate feedback load change according to the change of field pressure;and stepless speed regulation could realize by change opening angle of throttle.The hydraulic drive system with series-parallel combined double pumps and motors can meet the requirement of rape combine drive system,simplifies the structure of transmission system,as well as improve the working reliability of the transmission system. |
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