颗粒农产品非连续累计自动定量加料技术

    Discontinuous totalizing automatic quantitative feeding technology for granular agricultural products

    • 摘要: 为解决颗粒农产品定量加料精度不高、自动化程度较低等问题,该研究分析了市面上常见的颗粒农产品的物理特性,提出一种基于闭环控制算法的非连续累计加料定量方法,研制了一款针对颗粒农产品的动态定量加料设备,该设备的加料机构是通过滚珠丝杠螺母副和花键副来控制若干个可变容积的量杯结构,并通过复检机构检测加料实际质量。当加料实际质量与目标质量出现偏差时,通过闭环控制系统逐次修正定量加料机构的量杯容积,从而累计总量得到目标质量。试验结果表明,以定量加料600 g黄豆、红豆或绿豆为例,在量杯数量为5,设备转速为2 r/min的条件下,加料质量误差可控制在0.2%以内。该技术能够有效地减小动态定量加料产生的误差,定量精度远高于国家定量包装商品允许短缺量的要求。研究为颗粒农产品定量加料作业提供一种可行的技术方案。

       

      Abstract: Granular agricultural products can often be packaged quantitatively before sales. The speed and accuracy of material feeding are important indicators to evaluate quantitative feeding in quantitative packaging production lines. However, it is difficult to accurately and efficiently feed the granular agricultural products, due to the irregular appearance, uneven volume, and easy dispersion. In this study, discontinuous totalizing quantitative feeding was proposed, according to the volumetric and gravity (static weighing). A closed-loop control system was constructed with iterative learning. A dynamic quantitative feeding equipment was also developed for the granular agricultural products. The feeding mechanism of the equipment was composed of several measuring cups with variable volume under accurate control by the shaft. The reinspection mechanism of the equipment was composed of a reinspection weighing scale, removal, and unloading device, in order to inspect the actual quality of the feeding. The working procedure of the equipment was as follows. Firstly, the packaging target was evenly divided into several parts. And then one part of the target quality was quantitatively fed with each measuring cup during feeding. Finally, the actual quality of all measuring cups was totalized to obtain the packaging target. Furthermore, a gravity (static weighing) quantitative feeding was used to inspect the actual quality of the previous one before feeding to the next measuring cup in each group. The inspected error was used to adjust the volume of the next measuring cup in the same group. Since the packaging target quality was obtained by totalizing the feeding of several measuring cups, the volume of the following measuring cups was continuously corrected to make the totalizing feeding actual quality of the group of measuring cups in a group of feeding, regardless of whether there was an error in the first few measuring cups. This discontinuous totalizing feeding was integrated to improve the quantitative accuracy of the equipment. Taking 600 g of soybeans, red beans, or mung beans as examples, a series of quantitative feeds were carried out on the equipment. The experimental results showed that the feeding quality error was controlled within 0.2% when the number of measuring cups was 5 and the equipment rotational speed was 2 r/min. The error was effectively reduced during dynamic quantitative feeding. Particularly, the quantitative accuracy was much higher than that in the national standard requirement. The finding can provide a feasible technical solution to the high-accuracy quantitative feeding of granular agricultural products, such as traditional Chinese medicine pill packaging, quantitative sowing and fertilization, and quantitative feeding of granular fertilizers.

       

    /

    返回文章
    返回