芦苇收割机拨齿机构仿真设计

拨齿及传动装置是芦苇收割机中的关键部件。如何进行有效收割是芦苇收获的关键问题，而有效收割的关键是拨齿轨迹规划。通过对芦苇收割机的拨齿及运动机构进行研究，选择有急回特性的曲柄连杆机构来实现拨齿的弧形运动轨迹。依据收割需求，依据理论关系式计算出机构曲柄长度250 mm、摇杆长度330 mm、连杆长度690 mm和机架长度650 mm。然后，确定曲柄连杆机构驱动装置，考虑左右拨齿的曲柄转向相反、转速相同，且两曲柄始终保持180°角度差的联动要求，确定以相同尺寸链轮的链传动和相同尺寸齿轮的一级齿轮传动相互配合来实现该联动，根据需求，确定链和齿轮的关键尺寸。依据曲柄连杆、拨齿，以及链轮和齿轮尺寸，用Pro/E软件进行各零件绘制并进行装配，从而对设计机构进行运动仿真。通过参数调整，实现拨齿在连杆上的位置偏置75°时，有不错的收获效果，验证了设计的拨齿机构运动轨迹满足设计要求。该设计和仿真思路可对相关收获机的设计有一定的参考价值。 

Simulation Design of Gear Shifting Mechanism of Reeds Harvester

The key parts of reed harvester are teeth and transmission device.How to harvest effectively is the key problem of reed harvesting，and the key of effective harvesting is plan of teeth path.Based on research of reed harvester's tooth shifting and movement mechanism，crank connecting rod mechanism with quick return characteristics were selected to realize arc movement track of tooth shifting.According to harvesting demand，and with calculation of theoretical relationship，it was obtained that length of the crank was 250 mm，length of rocker was 330 mm，length of connecting rod was 690 mm，and length of frame was 650 mm.Then，driving device of crank connecting rod mechanism was determined.Considering linkage requirements that cranks of left and right shift geared turn in opposite directions，rotated at the same speed，and also two cranks always maintained 180 ° angle difference，chain drive and primary gear drive were determined to achieve the linkage.According to requirements，key dimensions of chain and gear were determined.With size of crank connecting rod，gear，sprocket and gear，the parts were drawn and assembled with Pro/E software，and then carrying out motion simulation of design mechanism.Through parameter adjustment，position of the gear on connecting rod was offset by 75 degrees could meet good harvest effect，and motion trajectory of designed gear shifting mechanism also met design requirements.The design and simulation ideas could be a reference for design of related harvesters.