| Sugar is an important strategic material,and its main raw material is sugarcane.Due to the climate,sugarcane is mainly planted in the hilly mountainous areas in the south of China,and the cane fields are small,scattered and sloping,so the existing large cut-off sugarcane combine harvesters cannot be widely used,resulting in the current mechanization rate of sugarcane harvesting in China is only 3.28%.The low efficiency of manual cane harvesting and high labor cost have squeezed out a large amount of cane profit space,coupled with the impact of foreign imported sugar and smuggled sugar on domestic sugar prices,resulting in a serious challenge and survival crisis for China’s sugarcane industry.Therefore,there is an urgent need to develop a small machine with high pass-ability,high mobility,and adaptable to slow and sloping,small-plot cane fields for cutting and spreading sugarcane with electro-hydraulic integration.Based on the modular cane cutter developed by the group,this paper designs a hydraulic system for this machine.The specific research contents are as follows:(1)According to the design objectives,the overall structure plan of the sugarcane cutter and its main components are determined based on the modular design theory,and its pass-ability,stability and steering operability are explained.(2)Determine the working principle of the whole machine of sugarcane cutter and the motion process of each actuator,clarify the technical requirements of each actuator,working condition requirements and hydraulic system design requirements,design the hydraulic system of the whole machine front wheel steering,the hydraulic system of the floating blade and the hydraulic system of the cane cutting mechanism for design analysis.The hydraulic system of the whole machine adopts the closed-core load-sensitive system composed of variable pump + load-sensitive valve.(3)Complete the selection and calibration of hydraulic motors,hydraulic cylinders and hydraulic pumps of each actuator,determine the maximum power of the whole machine as 46.66 k W through theoretical calculation,and select a 70 hp diesel engine as the power source of the whole machine.Determine the maximum total flow rate of simultaneous action hydraulic motor or hydraulic cylinder is 163.99L/min.(4)Mathematical modeling of the relevant control valves was carried out,while the simulation was verified using AMESim software.The simulation results confirm that the designed hydraulic system of the sugarcane cutter and paver meets the theoretical calculation results and design requirements.(5)Complete the prototype of the sugarcane cutter and paver,and design the relevant tests by combining the test conditions and hydraulic system performance requirements of agricultural machinery.Further verify that the designed hydraulic system of the modular sugarcane cutter and paver meets the operational requirements.In the static test of the sugarcane cutter and paver,the motor speed and hydraulic cylinder displacement of the prototype were tested,and it was concluded that they basically match with the theoretical design values and meet the actual operation requirements.In the field test,a ternary quadratic regression orthogonal rotation combination test scheme was designed,taking the actual forward speed v of the cane cutter,the cane cutter speed n and the internal inclination angle β of the cane cutter as the influencing factors and the head breaking rate as the index.Finally,the head breakage rate was 8.2% when the actual forward speed v of the cane cutter was 450mm/s,the rotational speed n of the cane cutter was 550r/min and the internal inclination angle β of the cane cutter was 12.5°.The whole machine was in good working condition during the test and reached the expected design requirements. |
