In view of the lack of systemic analysis for stepless transmission using noncircular gears, two basic noncircular gear units, an addition unit adopting differential mechanism and a multiplication unit applying a fixed...In view of the lack of systemic analysis for stepless transmission using noncircular gears, two basic noncircular gear units, an addition unit adopting differential mechanism and a multiplication unit applying a fixed gear train, are proposed. Then, the design methods of the noncircular gear pair of each unit, transmission ratio relationship, rotation angle relationship and key parameters with specific physical meanings are studied. The adjusting properties, composing strategy and varying range of transmission ratio etc. are investigated in detail for each unit. Following this, several examples of using a noncircular gear pair in the units and their manipulation technique are introduced.展开更多
Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is o...Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is one of the main limitations of configuration innovation.In the present study,epicyclic gear trains(EGTs)are applied to investigate mechanisms of 9-speed ATs.Then four kinematic configurations are proposed for automatic transitions.In order to evaluate the performance of proposed mechanisms,the lever analogy method is applied to conduct kinematic and mechanical analyses.The power flow analysis is conducted,and then transmission efficiencies are calculated based on the torque method.The comparative analysis between the proposed and existing mechanisms is carried out where obtained results show that proposed mechanisms have reasonable performance and can be used in ATs.The prototype of an AT is manufactured and the speed test is conducted,which proves the accuracy of analysis and the feasibility of proposed mechanisms.展开更多
针对深施型液肥穴施肥机存在损伤作物、穴口宽度大和喷肥效率低等问题,设计了一种深施型斜置式液肥穴施肥机。基于斜置式扎穴和参数反求求解设计思想,借助人机交互平台,设计关键部件扎穴机构,优化了机构的结构与工作参数,分析了喷肥针...针对深施型液肥穴施肥机存在损伤作物、穴口宽度大和喷肥效率低等问题,设计了一种深施型斜置式液肥穴施肥机。基于斜置式扎穴和参数反求求解设计思想,借助人机交互平台,设计关键部件扎穴机构,优化了机构的结构与工作参数,分析了喷肥针进肥接口运动轨迹。根据喷肥针入土、出土喷肥技术特点,运用差动轮系传动和空间凸轮机构的组合传动形式,设计了关键部件液肥分配机构,减少了输肥管路复杂的连接配置,构建了出肥软管接口运动模型,解析了满足于进肥软管接口协同运动机理。进行了深施型斜置式液肥穴施肥机田间性能检测试验,结果表明,该机扎穴性能优越,肥料喷射均匀,对作物的机械损伤小,穴口宽度、作物损伤率、施肥量和施肥深度分别为45.0 mm、0.3%、28.5 m L/次和102 mm,各项指标与前期设计差异较小,且符合农艺要求。展开更多
文摘In view of the lack of systemic analysis for stepless transmission using noncircular gears, two basic noncircular gear units, an addition unit adopting differential mechanism and a multiplication unit applying a fixed gear train, are proposed. Then, the design methods of the noncircular gear pair of each unit, transmission ratio relationship, rotation angle relationship and key parameters with specific physical meanings are studied. The adjusting properties, composing strategy and varying range of transmission ratio etc. are investigated in detail for each unit. Following this, several examples of using a noncircular gear pair in the units and their manipulation technique are introduced.
基金Supported by National Natural Science Foundation of China(Grant Nos.51975544,51675495).
文摘Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is one of the main limitations of configuration innovation.In the present study,epicyclic gear trains(EGTs)are applied to investigate mechanisms of 9-speed ATs.Then four kinematic configurations are proposed for automatic transitions.In order to evaluate the performance of proposed mechanisms,the lever analogy method is applied to conduct kinematic and mechanical analyses.The power flow analysis is conducted,and then transmission efficiencies are calculated based on the torque method.The comparative analysis between the proposed and existing mechanisms is carried out where obtained results show that proposed mechanisms have reasonable performance and can be used in ATs.The prototype of an AT is manufactured and the speed test is conducted,which proves the accuracy of analysis and the feasibility of proposed mechanisms.
文摘针对深施型液肥穴施肥机存在损伤作物、穴口宽度大和喷肥效率低等问题,设计了一种深施型斜置式液肥穴施肥机。基于斜置式扎穴和参数反求求解设计思想,借助人机交互平台,设计关键部件扎穴机构,优化了机构的结构与工作参数,分析了喷肥针进肥接口运动轨迹。根据喷肥针入土、出土喷肥技术特点,运用差动轮系传动和空间凸轮机构的组合传动形式,设计了关键部件液肥分配机构,减少了输肥管路复杂的连接配置,构建了出肥软管接口运动模型,解析了满足于进肥软管接口协同运动机理。进行了深施型斜置式液肥穴施肥机田间性能检测试验,结果表明,该机扎穴性能优越,肥料喷射均匀,对作物的机械损伤小,穴口宽度、作物损伤率、施肥量和施肥深度分别为45.0 mm、0.3%、28.5 m L/次和102 mm,各项指标与前期设计差异较小,且符合农艺要求。
