夹指链式残膜回收机脱膜装置设计与试验

针对现有残膜回收机脱膜困难的问题,该研究设计了一种夹指链式残膜回收机脱膜装置,主要由刮板总成、曲柄摇杆机构和膜杂分离机构等组成,可一次性完成脱膜、膜杂分离和输膜作业。为增加夹指随夹指链转过上收膜轮的过程中与刮板接触的次数,将刮板总成中的刮板设为双层,并通过作业过程分析对其结构参数进行设计;使用ADAMS软件对刮板末端运动轨迹进行仿真分析,并根据仿真结果对曲柄摇杆机构的杆件长度及安装角进行设计;通过对残膜受力情况的分析,确定了曲柄摇杆机构的安装位置;通过运动学分析获得了夹指不被漏刮时上收膜轮角速度与曲柄角速度比的最大值;为实现输膜与膜杂分离,设计了往复摆动式膜杂分离机构,并通过作业机理分析及性能试验对相关部件的结构参数进行设计。田间试验结果表明,当机具作业速度为4.5 km/h、刮板宽度为100 mm、曲柄回转中心与上收膜轮中心间的水平安装距离为290 mm、竖直安装距离为200 mm、上收膜轮角速度与曲柄角速度比为0.5、输膜筛相邻棒条间的安装距离为50mm时,残膜回收率为93.12%,脱膜率为98.2%,含杂率为16.08%,能够满足残膜回收机田间作业要求。研究成果可为相关装置的设计提供参考。

Design and experiment of film removing device for clamping finger-chain type residual film collector

Film-mulching cultivation technology could significantly improve the growth condition of crops and increase the economic benefits of agricultural production. However, the residual film in soil is very difficult to degrade, and there is no effective recovery method, resulting in the amount of residual film in farmland soil gradually increased. The residual film currently has a serious impact on the ecological environment of farmland soil. To solve this problem, domestic scholars have devised a variety of residual film collectors. The design of film removing device was one of the key points in the development of the residual film collector. However, the existing residual film collectors mainly adopts the structure of pneumatic, telescopic rod tooth and rotary scraper, which could easily cause secondary winding of residual film during the film removing process. Thus, a film removing device of clamping finger-chain type for residual film collection was designed in this study. The device was consisted of scraper assembly, crank-rocker mechanism and film-impurity separation mechanism, which could complete the work of film removing, film-impurity separation, and film transport at one time. In order to increase the contact times between the finger and the scraper when the clamping finger-chain moved upward, a double-layer arrangement structure of scraper was adopted in the scraper assembly, and the structural parameters were designed through the analysis of the operation process. The ADAMS software was used to simulate and analyze the motion trajectory of the endpoint of the scraper, and the length of each rod and the mounting angle of the crank-rocker mechanism were designed. Through the force analysis of residual film, the mounting position of the crank-rocker mechanism was determined. Through the kinematics analysis, the maximum value of the angular speed ratio between the upper film collecting wheel and the crank when the fingers were not scratched was obtained. In order to achieve the film-impurity separation and film transport, a film-impurity separation mechanism with reciprocating swing type was designed, and the structural parameters of related components were designed based on the operation mechanism analysis and performance tests. The field experiments results showed that the residual film recovery rate was 93.12%, the film removing rate was 98.2%, and the content rate of impurities was 16.08%, when the travel speed of the collector was 4.5 km/h, the width of scraper was 100 mm, the horizontal mounting distance between the rotation center of crank and the center of upper film collecting wheel was 290 mm, the vertical mounting distance between the rotation center of crank and the center of upper film collecting wheel was 200 mm, the angular speed ratio between the upper film collecting wheel and the crank was 0.5, and the mounting distance of the bar in film transport sieve was 50 mm, The results indicated that the film removing device could meet the field operation requirements of the residual film collector. The research can provide the basis and reference for the development of relevant residual film collector.