电驱式小区玉米膜上直插穴播机的研制与试验

为解决西北地区制种玉米机械化播种问题,针对制种玉米播种条件和农艺要求,设计了电驱式小区玉米膜上直插穴播机。重点对构成该机的核心部件前进速度补偿机构、限深机构、后轮高度调节机构等进行了设计、仿真。前进速度补偿机构是由转动导杆机构驱动平行四杆机构进行机具前进速度补偿来实现成穴器入土播种和出土期间水平位移差接近零;限深机构可保证穴播机播深合格率;后轮高度调节机构可根据平铺膜和垄作铺膜前轮与后轮的行走情况使机器保持水平,非作业时升高后轮可避免鸭嘴接触地表或撕裂地膜。并进行了大田试验,试验结果表明:前进速度补偿机构运行平稳可靠、振动较小,驱动的排种器鸭嘴插膜口小,穴孔和膜孔无错位,播深合格率较高;整机空穴率为1.1%,穴粒数合格率为93.2%,膜下播种深度合格率为90.1%,三项核心指标均达到了NY/T987—2006《铺膜穴播机作业质量》标准的指标;膜孔合格率为98.5%,可满足制种玉米播种的农艺技术要求和玉米播种机的基本作业质量标准要求。

Development and experiment of electric driving insert hill-drop planter on film for plot corn

Abstract: In solving the problem on the seed corn mechanization sowing in the northwest area and understanding the corn sowing conditions and agronomic requirements, an electric driving corn hill-drop planter with inserting on film in the plot was developed. The differential motor drives are installed in the front wheel shaft with the front wheel moving ahead. Also, the motor drives are used for the electromagnetic clutch to rotate. Whenever the clutch is switched on, the input power of the motor crank shaft sprocket is used through a different number of the teeth of the deceleration after the transfer to increase the speed compensation mechanism. The uniform rotation of the input crank guide rod achieves a non-uniform rotation that drives the non-uniform rotary motion of the parallel four-bar mechanism, which means that when the planter moves forward, the duckbill in the sowing period goes straight up and down relative to the ground. The sowing device assembly makes the toggle wheel move by the up and down movement of the brace, driving the wheel wrench to turn to take or discharge seeds, and to pull the trigger on the active duckbill to achieve the seed discharging. The sowing device components are attached to the sowing rod through the slider and spring damper. When the hard ground or rock spring damper is compressed, it protects the duckbill. When there is a leakage sowing, the sowing alarm installed on metering device will alarm the module to remind the artificial sowing. As part of the core components of the forward speed compensation mechanism, the depth limiting and rear-wheel height adjusting mechanisms were designed and simulated. The forward speed compensation mechanism consists mainly of crank rod, slider, guide rod, driving rod, driven rod, and bunch rod. The core function of attaining the forward speed compensation under the periodically rotating guide bar drives the parallel four-bar mechanism. Compensation under the buried and unearthed planting bars, which is near zero speed, promotes the corn growth around the bed (deficient in the upper bed and excess in the lower bed), makes the corn less damaged, and reduces the planting bar to tear the plastic film. Considering the tread of the front wheel of the planters is small, the seed sowing performance and the pass rate of sowing depth for the seed sowing device are affected by the ground roughness. Also, the corn seeds germinate better under the same sowing depth. With this, the depth limiting mechanism was designed. In meeting the demand of the film mulching and ridge tillage, the walking machine maintains the level, and when there is no operation the duckbill of the planter avoids touching the surface and tearing film, and the rear height adjusting mechanism designed is mainly composed of push rod, DC (direct current) linear electric push rod, rotating shaft, bottom bar and land wheel. In the perform test, the results showed that the hole rate was 1.1%, the qualified rate of seeds number per cavity was 93.2%, and the pass rate of sowing depth under the film was 90.1%. The three sowing core indicators have reached the standard of NY/T 987-2006 PU film dibbling machine operation quality, and the film hole qualified rate was 98.5%. The test results show the operation of compensation device is stable and reliable in the forward speed, which was placed on the 2 lines of symmetry and greatly reduced the vibration of the whole machine cycle. The film holes of the duckbill inserted were smaller, and hole and film hole have not slipped, and the qualified rate of sowing depth was higher. After encountering stones, the duckbill will not insert into it forcedly. The results of this study met the design and agronomic requirements as cited.