基于TRIZ-AD的集成式油菜气力精量排种装置设计

针对现有气力式播种机排种装置的传动和供气系统复杂、机械结构无法适配智能变量作业、气力供给风压消耗大且稳定性差等问题,该研究应用发明问题解决理论（theory of inventive problem solving, TRIZ）与公理化设计（axiomatic design theory, AD）方法,开展油菜气力精量排种装置设计。首先使用TRIZ技术成熟度预测和进化定律分析,阐明了排种技术发展阶段和进化路径及潜力;其次建立基于TRIZ和AD集成的设计过程模型,求解时在功能域到结构域映射过程中引入TRIZ工具,采用“冲突解决原理”解决现有排种装置中涉及的传动方案、供气系统矛盾冲突,分析对改善结构参数有用的发明原理和对应的方案,最终确定电机直接驱动排种盘和风机内置气室的解决方案,构造并求解其原始设计矩阵,并通过独立公理和信息公理判断该解决方案的合理性及最优化。最后进行电机风机集成式油菜气力精量排种装置设计,确定电机风机同侧排布技术方案,集成电机驱动简化传动,集成风机取消输气管道降低风压损失。台架试验结果表明,设计的集成式排种器排种性能满足油菜单粒排种要求,吸种负压绝对值取1.0～2.0 kPa、作业速度小于7 km/h时,排种合格指数均大于90%,且合格指数达到90%需要的风压低于现有排种装置风机和输气管道布局所需风压。本研究可为气力式排种器设计提供思路和参考。

Design of the integrated precision pneumatic seed metering device for rapeseed using TRIZ-AD

A pneumatic seed metering device is required for the high speed and intelligent variable operation in recent years. However, the existing complicated transmission and pneumatic system and mechanical structure cannot fully meet the large-scale production of pneumatic supply with the high stability, due mainly to the pressure loss caused by a curved pipe. In this study, the invention problem problem-solving theory (TRIZ) and axiomatic theory design (AD) methods were applied to carry out the innovative design of a pneumatic seeding device for rapeseed. Firstly, the seeding maturity prediction and evolution were used to clarify the development stage, evolution path, and potential of seed metering using TRIZ technology. The existing seeding technology was in a recession recovery period, while the evolution of the technology system was in line with the S-curve evolutionary law and evolutionary model. The future seed metering device was preferred for the integration in the simple, microscopic, controllable, and automated evolutionary path. Secondly, the design process model was established using the integration of TRIZ and AD. TRIZ tools were introduced in the process of mapping functional to structural domains. Among them, the "conflict resolution principles" was adopted to solve the contradiction and conflicts of the transmission and pneumatic systems in the existing seed metering device. The invention principles were selected to optimize the structural parameters. Finally, the motor was utilized to directly drive the seeding disk and the built-in air chamber of the fan. The original design matrix was developed using independent design axioms and the minimum entropy. An innovative system was designed to integrate the motor- fan with the pneumatic seed metering device for rape. The trial production and processing were performed on two technical implementation schemes. The motor fan was determined to arrange on the same side after optimization, particularly for the better airtightness and structural stability. The integrated motor drive was used to simplify the transmission, whereas, the integrated fan was to eliminate the gas transmission pipe, in order to reduce the wind pressure loss. As such, the improved transmission and pneumatic system were required only a small space without the additional power. The test results show that the integrated seed metering device was fully meetmet the requirements of single seed metering. A better performance was achieved in the qualified index is more than 90%, even reached reaching up to 99.82%, when the absolute value of suction negative pressure was 1.0-2.0 kPa and the working speed was less than 7 km/h. The required pressure for the qualified index of 90% was lower than before. The innovative design of the pneumatic seed metering device was integrated the power and pneumatic sources, which was were in the line with the technological system evolution path, individual start and stop of the seeding unit without any influence on the rows. More importantly, the mechanical structure and transmission were better matched for the development trend of intelligent variables. This finding can provide an innovative design idea and references for the design of a pneumatic seed device.