Research On Shift Law And Shifting Automatic Device Of Corn Harvester

Corn is the main source of largest food crop,feed and industrial raw materials in our country.In order to shorten the harvest period and improve harvest efficiency,the corn harvester is widely used.However,when the corn harvester completes different tasks,the driver needs to frequently shift gears to adapt to different working conditions,which greatly increases the driver's labor intensity.At the same time,corn harvester there are problems such as high fuel consumption,insufficient power,poor matching of gears and corn harvester speed.This article takes the 4YZ-4B model corn harvester as an example.According to the shortcomings of this model corn harvester,in order to reduce the labor intensity of the driver,let the driver more focus on farming,thereby improving farming efficiency and improving fuel consumption.And the problem of corn harvester flameout,this subject has carried out the following three aspects of research,the main research contents are follows:(1)Research on shifting laws.The research of shifting laws is an important theory of vehicle automatic shifting research.The advantages and disadvantages will directly affect the shift performance of the corn harvester,and then affect the power,economy and driving comfort of the corn harvester.Therefore,based on the research and analysis of the shifting characteristics of the corn harvester and according to its operating characteristics,three sets of different shifting rules are formulated: when driving at no load,the goal is to improve power,and the corn harvester speed and throttle opening are used as controls parameters,studied the best dynamic automatic shift law;when driving at no load,to improve the economy as the goal,with the vehicle speed and throttle opening as the control parameters,studied the best economic automatic shift law;farming driving In order to meet the requirements of dynamic performance and improve economic efficiency,the corn harvester's driving speed,throttle opening and corn harvester weight are used as control parameters to study the best economic automatic shifting rules.And according to the above three working conditions,determine the best shift point under the three conditions.(2)Research on automatic shifting device.Based on the research of shifting laws,an automatic shifting device was developed.The device mainly includes signal processing devices such as position sensors,pulse encoders,programmable logic controllers,andhydraulic related devices such as hydraulic pump stations,solenoid valves,and hydraulic cylinders.The main working process is to first use the output speed of the gearbox to simulate the driving speed of the vehicle and measure it,and secondly,convert the measured speed signal into a pulse signal and pass it to the PLC.Then the PLC recognizes and judges the pulse signal Switch gears.Finally,through the assistance of the hydraulic system,the automatic conversion of gear hydraulic assistance is carried out.(3)Construction of the test stand for the automatic shift gearbox of the corn harvester.In order to verify the feasibility of the shifting device,a test stand for the automatic shifting gearbox of the corn harvester was built,and the shifting device and related transmission parts were separated into a system to simulate the actual vehicle shifting process of the corn harvester.The test bench first performs gear shift debugging and calculates the transmission ratio for each gear by manual adjustment,and then performs automatic gear shift debugging.Through test verification,each gear can be reasonably switched,and the ratio of input and output speeds basically conforms to the gear ratio.The automatic shifting device can continuously perform shifting for more than 2 hours.The research of this subject provides a set of shifting theory and a theoretically feasible shifting method for the 4YZ-4B corn harvester to realize automatic shifting,which reduces the shifting time,reduces the labor intensity,and makes the driver more focused on agriculture.The work will also help to promote the development of automatic shifting of agricultural machinery in China and promote the improvement of the industry.