ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

In order to meet the requirements of precision planting and improve the seeding quality of potato seed metering device, a kind of doublerow cross spoonbelt potato precision seed metering device was designed. The overall structure and working principle of the seed metering device were illustrated and analyzed. The optimal design of structural parameters of key components was conducted, such as the doublerow cross seeding assembly, the driving assembly and the vibration cleaningseed assembly. To improve the working performance of the metering device, obtain the best operation parameters, the quadratic general rotary unitized design was carried out with the rotational speed and the amplitude of seed metering device as the experiment factors and the seeding qualified index, the relaying seed qualified index and the missing seed qualified index as the experimental indexes. Based on experimental data, a mathematical model was built by using the Design-Expert 6.0.10 software, and the experimental factors were optimized, the best combination was achieved. Test results showed that as the rotational speed was 31.5r/min, the amplitude was 11.7mm, and the seeding qualified index was 89.92%, the improved metering device exceeded the original one by 19.9%, the relaying seed qualified index was 5.12%,and the missing seed qualified index was 4.96%. On the basis, the metering adaptability filed 〖JP3〗test was carried out, and then test results showed that the seeding performance of seed metering device to all size grades of potato seeds could meet the requirements of precision planting. The results can provide the guidance and direction for the research of potato precision seeder and its key parts.