玉米勺式排种器变速补种系统设计与试验

针对玉米勺式排种器出现的漏播问题,设计了一种变速补种系统,该系统采用光电传感器在偏离出种口20°位置进行提前检测,漏播发生时由步进电动机改变排种器转速越过空种槽达到实时补种的目的。为了使变速补种系统具有通用性,选取具有一定代表性的玉米籽粒外形形状品种:久龙5号(球形)、九单57(锥形)和郑单958(矩形),以不同转速作为试验因素,运用EDEM软件和排种器性能试验台进行排种性能研究。仿真结果表明:当转速不超过23.1 r/min时,排种性能受变速影响不超过2%,在转速达到27.7 r/min时,变速种子抖落现象明显;在转速达到32.3 r/min时,变速时种子会出现严重的抖落现象;试验结果表明:具有变速补种系统的勺式排种器转速处于13.9~23.1 r/min时,漏播率不超过1.4%,平均补种率达到89.95%,播种率达到98.7%。在转速为27.7 r/min时,比不具有变速补种系统的勺式排种器漏播指数降低10.4%,补种效果最为显著,在转速达到32.3 r/min时,补种效果不显著;3种玉米品种的排种性能优劣次序为:球形、矩形、锥形。

Design of Reseed Shift Speed System of Scoop-type Metering Device of Corn

Aiming to solve the problem of leakage webcasting for corn seedmeter, a reseed shift speed system was designed, which used photoelectric sensor to early detect at the position deviated from the kinds of ports by 20°, and a stepping motor changed seedmeter when leakage occurred sowing speed over the empty slot to achieve real replant seed purposes. In order to make the shift to replant system have the versatility, specifically representative corn grain appearance shape varieties were selected, including Jiulong No.5 (spherical), Jiudan No.57 (cone) and Zhengdan No.958 (rectangle). Taking different speeds as test factors, the seeding performance was studied by using of EDEM software and seeding performance test bed, simulation results showed that when the speed was not exceeded 23.1r/min, the impact of speed shifting on seeding performance was not more than 2%, when the rotational speed reached 32.3r/min, serious shaking phenomenon of seed would happen. Test results showed that the scoop-type replant seed metering systems equipped with variable speed when the rotation speed was 13.9~23.1r/min, drain sowing rate was not exceeded 1.4%, the average replant rate was 89.95%, seeding rate reached 98.7%;at the speed of 27.7r/min, compared with the original scoop-style metering, its row seed sowing leakage index was decreased by 10.4%, the effect of replanting was the most obvious;when the speed reached 32.3r/min, the effect of replanting was not obvious;the seeding performance of three corn varieties showed a decreasing trend of spherical, rectangular and cone.