作者：徐海卫1, 谢驰2, 曹江萍1, 李刚1, 赵欣2
作者单位：1. 四川中测量仪有限公司, 四川 成都 610021;
2. 四川大学锦城学院, 四川 成都 611731
关键词：茶叶揉捻;受力模型;压力检测;调节控制
摘要：
茶叶的物理特性和品质常受到揉捻压力大小的影响,通过对茶叶在揉捻机桶中的受力情况进行分析,建立茶叶在桶式揉捻机揉捻过程中的受力模型,求解出最佳的施压模型和揉捻盘转速之间参数关系。通过自动控制揉捻过程,并在茶叶揉捻过程中进行揉捻压力的实时监测,将监测值与建立的施压数学模型进行计算后,自动调整茶叶揉捻压力与揉捻盘转速,实现满足茶叶揉捻加工工艺的自动化作业要求。试验仿真表明:在揉捻桶可调节转数上限60 r/min,可调节压力上限800 N,揉捻桶直径为550 mm时,揉捻机最佳揉捻茶叶质量为500～4 000 g,茶叶破损率10%。
Research on the optimal regulation control of barreling pressure for the tea
XU Haiwei1, XIE Chi2, CAO Jiangping1, LI Gang1, ZHAO Xin2
1. Sichuan Measuring Instrument Technology Company, Chengdu 610021, China;
2. Jincheng College of Sichuan University, Chengdu 611731, China
Abstract: Tea physical properties and quality are often influenced by the rolling pressure in tea production. In this paper, a mechanical model for tea in the rolling process of barrel-shaped tea rolling machines was established to solve the optimal parameter relationship between the force model and the speed of the rolling plate based on the analysis of the stress condition of the tea in the rolling machine. It comprises the following steps: first, automatically control the rolling process and monitor the rolling pressure during the rolling process in real-time; second, calculate the monitored value with the mathematical model for stress; third, automatically adjust the rolling pressure and the speed of the rolling plate to meet the automatic operation requirement on tea rolling process. The simulation results show that, for the barrel-shaped tea rolling machine, the adjustable speed limit is 60 r/min, the adjustable pressure limit is 800 N and the barrel diameter is 550 mm. The tea breakage rate is less than 10% when the tea kneaded is between 500 g to 4000 g in weight.
Keywords: tea rolling;force model;pressure measurement;regulation control
2015, 41(10): 112-116 收稿日期: 2015-03-21;收到修改稿日期: 2015-04-13
基金项目: 国家863基金资助项目(2012AA10A508)
作者简介: 徐海卫(1960-),男,四川成都市人,高级工程师,主要从事智能机械、测试技术、茶叶机械、节能技术等研究。
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