The shortage of labors for livestock farming is an apparent problem in Taiwan now. How to operate automatically the daily works on the farm by limited labors becomes a very important issue. Meanwhile, it takes time and requires a lot of labors for forage harvesting and processing . In order to solve forage overproduction and supply steadily corn silage to a farm, the objective of this study was to design and evaluate an automatic packing system for making corn silage in the plastic bags. This system could also reduce the packing time and save labor, and improve the quality of corn silage.
Physical properties of forage corn were determined and analyzed as a design basis for prototype of packing machine. Moisture content of experimental samples of forage corn, grown in spring, was 73%. The average length and bulk density of samples were 12.8 mm and 0.172, respectively. In compression test, lots of water leaked out as gauge pressure reached 50 kg/cm2. Hence, design criterion would be based on gauge pressure with 40 kg/cm2. The regression equation, with the coefficient of correlation of 0.9949, was obtained The average thickness of the PE bag used for storing corn silage was 0.12 mm. The tensile strengths in lateral and longitudinal directions were 134 kg/cm2 and 140.4 kg/cm2, respectively. After being sealed by heat, tensile strengths were changed to 144.9 kg/cm2, 129.8 kg/cm2, and 114.4 kg/cm2 for 2, 4, and 6 layers, respectively. The smallest tensile strength of 6 layers was greater than the compressive pressure.
For the prototype, the average rate of packing was 19 sec/bag and successful packing rate was 90%.目前臺灣農牧工作人力短缺，能使用的人力資源有限，所以如何將工作自動化是很重要的課題，而現今儲存包裝牧草乃是一項既費時且耗費人力的工作。為了解決牧草生產過剩並穩定供給酪農青貯料，本研究目的在設計與製造一部青割玉米太空包自動封裝機，以降低太空包封裝時間，減少對人工之依賴及提高青貯品質。
試驗初期，先對青割玉米做基本物性之量測與分析，以此作為太空包封裝機之設計依據；取樣量測的春作青割玉米其含水率73%，總平均之細切長度12.8 mm，平均虛表比重0.172。在壓縮密度試驗下，當錶壓力達至50 kg/cm2 時，壓縮缸內之青貯玉米已有大量水份滲出，設定壓縮青貯包裝時的最大錶壓力應為40 kg/cm2，求得其迴歸方程式為壓縮比相關係數為0.9949。青貯用PE袋，平均厚度為0.12 mm，抗拉應力横向為134 kg/cm2 、縱向為140.4 kg/cm2 。熱封後之抗拉應力兩層為144.9 kg/cm2 、四層為129.8 kg/cm2、六層為114.4 kg/cm2 。其中最小的六層抗拉應力仍遠大於壓縮密度壓力。
自動封裝雛型機的封裝平均速度為19秒/袋。封裝成功率為 90 %。目錄
摘要 I
ABSTRACT II
目錄 III
圖目錄 VII
表目錄 XI
第一章 前 言 1
1.1研究動機 1
1.2研究目的 3
1.3研究項目 3
第二章 文獻探討 6
2.1加入WTO對產業之影響 6
2.2青貯之定義 7
2.3青貯之歷史 7
2.4芻料作物品種 8
2.5青貯之優缺點 11
2.6青貯發酵過程 12
2.7青貯料常見問題 15
2.8青貯材料之細切程度 17
2.9青貯材料水分含量之調整 17
2.10青貯封裝應注意事項 18
2.11青貯品質評估 18
2.12青貯方式 23
第三章 材料與方法 28
3.1大型青割玉米太空包青貯自動化封裝系統設計概念 30
3.2小型青割玉米青貯封裝雛型機構想 33
3.2.1壓板設計 33
3.2.2封裝設計 36
3.2.3小型青割玉米青貯封裝雛型機設計 41
3.2.4作業程序控制系統 46
3.3物性試驗 47
3.3.1青割玉米與塑膠袋之物性試驗裝置 48
3.3.2青割玉米之相關物性試驗方法 51
3.3.3塑膠袋之選用 56
3.3.4塑膠袋相關物性試驗方法 58
3.4自動封裝測試 60
第四章 結果與討論 62
4.1小型青割玉米青貯封裝雛型機介紹 62
4.2物性試驗 65
4.2.1含水率 66
4.2.2細切長度 68
4.2.3虛表比重 70
4.2.4靜止角 70
4.2.5摩擦係數 70
4.2.6青貯料壓縮密度 71
4.2.7發酵之溫度與膨脹壓力 73
4.2.8塑膠袋之抗拉應力 75
4.3自動封裝測試 77
第五章 結論與建議 80
5.1結論 80
5.2建議 82
參考文獻 83
附錄 86
附錄1 小型青割玉米青貯封裝雛型機PLC控制階梯圖 86
附錄2 數據記錄器 ( 21X-Data logger )量測溫度之程式 91
附錄3 聚乙烯薄膜特性 93
附錄4 小型青割玉米青貯封裝雛型機細部機構圖 94
附錄5 物性試驗數據 114
附錄5.1 青割玉米含水率(%) 114
附錄5.2 青割玉米細切長度（mm） 118
附錄5.3 青割玉米虛表比重 121
附錄5.4 青割玉米靜止角( °) 122
附錄5.5 青割玉米摩擦係數 123
附錄5.6 青割玉米壓縮比 125
附錄5.7 塑膠袋抗拉力 126
附錄5.8 塑膠袋熱封口抗拉力 12
