油菜联合收获机串并联组合式液压驱动系统设计与试验

针对传统油菜联合收获机运动部件多、机械传动路线长且结构复杂等问题,设计了1套应用于4LYZ-1.8型油菜联合收获机的串并联组合式双泵多马达液压驱动系统,通过液压系统测试确定了负载敏感系统节流阀开度与转速间关系;采用正交试验研究割台复合推运器转速、脱粒滚筒转速、抛扬机转速、强制喂入轮转速对负载敏感系统总功耗的影响;开展功耗分析试验对主要工作部件所在回路的功耗进行测量。正交试验方差分析表明:脱粒滚筒转速对负载敏感系统总功耗影响极显著,割台复合推运器转速、旋风分离筒入口风速对总功耗影响显著。液压回路功耗分析试验表明:油菜平均喂入量为1.5kg/s时,割台平均功耗为1.68kW,强制喂入轮平均功耗为1.00kW,脱粒滚筒平均功耗为5.11kW,抛扬机及输送装置平均功耗为2.28kW,风机平均功耗为1.80kW。田间试验表明:串并联组合式双泵多马达液压驱动系统可适应油菜联合收获机的作业要求,能根据不同作业工况实现无级调速。

Design and test of series parallel combined hydraulic drive system for rapeseed combine harvester

A set of hydraulic drive system with series-parallel combined double pumps and motors was designed to solve the problems of many moving parts and a long mechanical power transmission line of traditional rapeseed combine harvester. The system was applied in 4LYZ-1.8 rapeseed combine harvester. The relationship between throttle position and rotate speed was determined with testing hydraulic system. Orthogonal experiments were performed to study effects of header speed,cylinder speed,throwing machine speed and the speed of forced feeding roller on the power consumption of load sensitive system. The power consumption of circuits with main components was measured based on the experiment of power analysis. Results of analyzing variance of orthogonal experiments showed that power consumption of load sensitive system was significantly sensitive to the speed of threshing cylinder. The speed of cyclone separation tube inlet and the speed of header significantly affected the power consumption. Results of analyzing power consumption of hydraulic circuit showed that when the average feed rate was 1.5 kg/s,the average power consumption of five concerned parts including header,forcible feed rotor,threshing cylinder,throwing machine (conveying appliance was belonged) and fan was 1.68 kW,1.00 kW,5.11 kW 2.28 kW and 1.80 kW,respectively. Results of the field experiment of rapeseed combine harvester conducted in Huazhong Agricultural University indicated that the hydraulic drive system constructed can meet the working demand of rapeseed combine harvester,realize the regulation of stepless speed,and adapt different operation conditions. This study can simplify the structure of transmission system for rapeseed combine harvester and offer the reference for the power distribution of different components.