联合收割，脱粒和分拣系统的优化用以降低玉米损失【中文6900字】
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联合收割，脱粒和分拣系统的优化用以降低玉米损失【中文6900字】,联合,收割,脱粒,以及,分拣,系统,优化,用以,降低,下降,玉米,损失,中文
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【中文 6900 字】联合收割，脱粒和分拣系统的优化用以降低玉米损失Roohollah Mohammad Sanabadi Aziz1，Sherwin Amini2摘要：用联合收割机收割玉米会导致一定程度的损失，从而降低利润;虽然这种损失不能完全消除，但可以控制在合理的程度。准备用于收获玉米的联合收割机是一个包括更换收割头和凹入以及盖板放置在脱粒滚筒上的过程。收获玉米的一个主要障碍是防止谷物损失，谷物损失主要发生在联合收割机头（将玉米穗轴与秸秆分离时）以及脱粒滚筒和凹面（因为玉米芯断裂）的收获过程中。目前的研究是在种子和植物改良研究所，玉米和饲料作物研究部门的一个 400 英亩的农场中进行的，其前提条件是脱粒滚筒转速为 750rpm，作物含水量为干基的 11.6。作物产量和测量的谷物损失量表明，当使用传统的施加垂直力来分离茎的头部时，收获期间谷物损失的程度变得过大;这些头部造成大量的作物损失。本研究的结果表现在联合刀杆上;因此，为了减少联合收割机收割损失，伊朗制造的联合收割机应该进行重大修改。在这方面采取的第一步是设计和实施对机器的两个主要部分即“玉米头”和“进料器单元”的必要修改。关键词：玉米联合收割机 减少 收割机联合 改造脱粒鼓和凹槽喂料机组1.简介世界上越来越多的人口面临粮食短缺的问题，因此需要扩大玉米等高产作物的生产，以克服这一问题。就全球面积而言，玉米排在小麦和大米之后。玉米产量在过去几年中已经超过了小麦和水稻的产量，在农产品中排名第一（Tajbakhsh，1996 ）。农作物的机械化收割一直是农民的目标。收获的目的是及时收集谷物及其与谷壳和其他废物部分的分离，尽可能以最高的质量和最小的损失量。在这方面，选择正确的采伐方法和适当的设备取决于作物类型，栽培方法和气候条件（Sirvastava 等，1990）。使用联合收割玉米时的玉米损失率取决于多种因素，如谷物的含水量，环境温度，农场条件（停滞），联合条件（新的或生锈的）和驾驶员的经验水平。这些因素一起或分开，可能会大大增加粮食损失。除了采用适当的收获机制之外，了解上述因素可以将损失率降低到合理的程度。 Behrouzilar 等人。（1995 年）对联合收割谷物和谷物的作物损失率进行了研究，并计划确定全球作物损失范围。他们评估了联合收割的谷物和谷类作物造成作物损失的因素，并得出结论，在伊朗，这一比率高于全球标准为 4-5。 Price 等人在研究油籽商业收获中的谷物损失时发现，（1996）发现理想的谷物损失可以在 2到 5左右。在伊朗正常的气候条件下，也录得20-25的损失（Anonymous ，1997 ）。随着联合进给率的增加，火箭的整体损失。原因是稻草人超载（Navid 等，2004 ）。在另一项研究中，测量了进展速度，脱粒滚筒的圆周速度，圆筒和副圆筒之间的空间，筛孔的大小，风扇速度和水分含量等参数（Rahama 等，1999）。研究人员还测量了在平台，脱粒滚筒以及分离和清洁系统中发生的任何形式的损失;他们报告的平均损失为 12。在另一项研究中，据报道联合收获的平均损失为 3.4 - 1.5与平台损失有关（Bukhari et al。，1983 ）。由于秸秆转移到分离和清洁系统的量减少，使用分离平台可增加 50-100的联合能力（Tado et al。，1998）。为了防止联合收割机的谷物损失和玉米谷壳的去除，需要将牵引链轮和锉刀棒调整得彼此更接近。集约化链条速度和牵引链轮速度在低性能农场中也需要增加，以便联合投入增加，其最大产能不会下降（Hoffman，2004 ）。根据作物条件调整标题是防止收获损失的重要一步（CampbellAlswager ，2003）。据报道，平台损失相当于联合收益损失总额的 50（ShahrestaniMinayi，2001）。高圆筒旋转是造成谷物破损和玉米棒破碎的另一个主要因素（Maier Parsons，1996）。机械化是农业发展的重要组成部分;自动化，适当的机器使用和机器技术的最佳使用可以提高效率，降低成本并提高生产率。为了保证国家玉米供应的自给自足，玉米生产过程中的所有领域应该以最高效率运行。由于目的是增加玉米产量并最大限度地减少进口（几乎为零），所以不应该容忍任何损失 - 特别是在收获阶段，可能会受到高比例的谷物损失。2.材料和方法该项目旨在优化联合收割机头系统，并实现玉米生产中的最小谷物损失;因此，第一步是购买玉米联合收割机以研究和分析其系统。然后确定在头部发生的玉米损失的来源以及系统中发生的其他类型的损失，以便在考虑所有因素的情况下确定它们的贡献机制，然后准备对现有头标进行标准测试和评估。下一阶段是检查联合收割机的运行机制，并根据联合收割机出现损失的原因对其进行修改以实现最小化目的。最后一步是对农场修改后的联合收割机头进行试运行，以便检查修改后的粮食损失程度，并将其与以前的状态进行比较。检查组合标题被检查的系统是可以安装在约翰迪尔 955 联合收割机上的 4 排玉米头。这个头被设计用来将玉米棒从茎秆中分离出来，然后将它们喂给装置。这个头有4 行，彼此间固定的距离为 75 厘米。该系统的主要部分是：a）框架b）电力传输系统c）收割机（玉米切割机）d）谷物输送机玉米头技术规格：所需功率：45 马力输入旋转：600 rpm 行数： 4收获率：每 8 小时 4 英亩重量：1000 公斤长度：320 厘米宽度：280 厘米身高：130 厘米图 1.玉米头的概况设计并提出一个合适的机制在项目的这个阶段，首先检查直接与作物接触并造成玉米损失的头部机制; 然后根据设想的机制，考虑到被检查的头部部件的功能进行了必要的修改。检查组合头的进料器单元机构当联合收割机沿着农场运行时，农作物在喂给单元，然后将玉米棒从秸秆中分离出来。进料单元负责分离过程; 该装置的可移动部件从机械嵌入式齿轮箱获得动力。能够分离和喂入玉米芯的部分如下：图 2.馈线单元机构U 形框架刀杆链式输送机构链条张紧器弹簧机构链轮稻草步行者变速箱饲养机构（现有联合收割机头）馈线单元部分可分为固定部分和可移动部分两大类。 固定部分包括 U 形框架，链条紧固器弹簧，刀杆和吸管助行器。活动部件包括链条，滚子链条和链轮。 动力传动系统向变速箱传递动力。从茎中分离玉米芯玉米头是由工厂设计的，当安装在联合收割机上时与农场形成一个攻角。被检查的四行玉米头还拥有三个顶盖，当联合收割机在田间移动时，玉米秸秆直接进入进料器单元。因此，当联合收割机沿着玉米田移动时，玉米秸秆流入馈线单元。直接涉及将玉米棒从茎上分离出来的部件是切割条（1）和链轮（2 ）。如前所述，刀杆放置在 U 形框架上，两个链轮也放置在框架下。链轮通过其可动齿轮相互转动。链轮旋转的方向被设计为使得相对于每个链轮的相反旋转将茎向下（进入切割条）。鉴于链轮的圆锥形状，在流入进料器单元时，玉米秸秆不会立即接触链轮;相反，它们在通过进料器单元时仅逐渐暴露于链轮。链轮的安装方式可以将玉米秸秆拉入切割棒中。根据收获的玉米芯的尺寸和大小调整切割器棒之间的空间，使得玉米棒不能自由地穿过这些空间;此外，由于链轮的叶片彼此重叠，所以茎杆继续被拉伸，并且玉米芯因此与茎分离。玉米棒的末端沿其自身轴线断开，以使玉米芯耳朵也从茎上松开。图 3.从茎中分离玉米棒的系统将玉米棒输送到进料器一旦从茎中分离出来，应将玉米棒输送到脱粒滚筒和凹部。 这种移动是通过三台输送机完成的，其中两台安装在联合收割机上，另一台安装在联合收割机内。 一旦农作物完全分开，它们应该被运送到联合收割机并收集起来; 然后它们通过传送带被送出。 第一台输送机（“谷物输送机”）安装在进料装置中。直接涉及将玉米芯输送到进料单元的机器部件包括：输送链条电机滚子链条移动滚子链条套在链条上图 4.谷物输送机建议减少玉米损失的机制如前所述，秸秆被玉米头中的链轮拉下来; 玉米芯也迅速被拉下来，它们卡在切割器棒之间并与茎分离。图 5.减少玉米损失的建议机制在现有的头部中，当将穗轴与茎分开时，沿着它们的纵向轴线拉动穗轴，这在玉米穗轴的基部上施加垂直的力;结果，玉米穗轴从基部破裂并且玉米也是 与棒子分开。图 6.玉米棒沿其纵轴断裂我们提出的机制旨在减少玉米芯从茎中分离出来时玉米的损失。由于玉米棒与玉米芯分离的主要原因是沿着玉米棒的纵向轴线施加的垂直力，因此本研究旨在修改当前的机制，并且实现最小化施加在玉米棒上的力的机制。一旦对将穗轴与茎分开的机构进行了必要的修改，拉力的方向以及因此分离偏离沿着穗轴的轴线，使得可以容易地将穗与穗分离，而没有不必要的损失发生冲击或振动。后者可以通过在切割棒的高度之间创建差异来完成。这些修改有三个好处：由于以更适当的角度施加力，将玉米棒与茎分开更容易并且需要更少的力量和力量。碰撞力的减小在防止玉米棒从茎分离的阶段期间防止玉米的损失非常有效。对谷物施加的力的方向已经改变 - 又一次改变有助于减少玉米损失。茎秆在它们与玉米棒的交界点处被打破（点 A）; 结果，由于它们也连接到茎上，所以穗轴也与穗轴分开。因此，如果在分离阶段，茎杆在其与穗轴的交界处断裂，则所有的穗轴也将破裂。很显然，减少联合收割机（尤其是脱粒滚筒和凹面）的废物投入会对操作质量产生积极的影响。在切割棒的高度上创建变化会改变施加在玉米棒端点上的 F 力的方向，使得 F 不再沿着玉米棒的轴线施加; 因此，沿轴线方向施加的力成为 F 的一部分。建议减少损失的机制如前所述，可以通过将轴向拉力减小到可能的最小有效程度来实现减少损失量，这意味着在进料器单元中的切刀棒的高度之间应该产生变化。 为了产生这种差异，填料板安装在切刀杆下方，以便将其放置在其他切刀杆的上方。图 7.填充板应该注意的是，链式输送机构和链条张紧器弹簧机构也位于刀杆上。 移动刀杆的位置也重新定位了这些机制; 因此，应该对所有三个部分进行更改：创建切割条高度的差异为了测试减少的玉米损失率，在切割杆高度之间创建的预期差异是 10 和15mm; 用于产生这种高度变化的填充板具有 5mm 的直径。图 8.馈线单元框架玉米头有 4 排，即四个分离机构; 一个机制接受 10 毫米的高度变化，另一个机制接受 15 毫米的高度变化，其他机制保持完好，以便可以检查每个收获路径的损失量，并且高度变化量对谷物损失程度的影响可以 被测量。图 9.切刀条重新定位链条张紧器弹簧机构链条张紧器弹簧放置在切刀条的顶部; 因此改变刀杆的位置也重新定位了这个弹簧。 链条张紧器弹簧只能垂直移动; 因此，该机构本身不会被修改，相反，将该机构安装在 U 形框架上的螺钉只会比其之前的位置高出 20mm。图 10.链条张紧器弹簧机构粮食输送链机制的安装和设置输送链机构也放置在刀杆的顶部; 因此，改变刀杆的位置也会重新定位该机构。 如前所述，谷物输送链机构由两个滚子链（电机滚子链和可移动滚子链）和一个链条组成，每个馈送单元包含两个谷物输送机构。 活动滚子链置于 L 形紧固件弹簧机构上， 移动后者导致可移动滚子链的修改和重新定位。 谷物输送机的电机滚子链条沿齿轮箱输送机链条的活动齿轮轴线定位。 考虑到一旦切刀条的位置发生变化，电机滚子链也应该沿着上述轴重新定位，轴的长度应该被调整，并且适当的填充垫应该被设计用于精确调整空间图 11.将链条机构安装在供纸单元框架上如前所述，仅在馈线单元中存在的四个单元中进行修改; 在其中一个单元中，一个刀杆位于相邻刀杆上方 10mm 处，另一个单元中另一个刀杆位于相邻刀杆上方 15mm 处。 因此，变速箱输送链的可动齿轮的轴线长度应增加20mm。图 12.当轴的高度变化时安装齿轮箱该轴被焊接到齿轮箱的中心，被移除; 设计一个更合适长度的新轴并将其焊接到齿轮箱上。 仅对标题进纸单元的四个单元中的两个进行修改。图 13.安装链轮和齿轮箱使用直径为 5mm 的填料垫片将滚子链安装到所需的高度。 本研究采用 10和 15mm 的样本高度变化。 为了将输送机的电机滚子链放置在供料单元的两个选定单元中，一个单元使用两个填充垫圈，另一个单元使用两个填充垫圈。图 14.海拔高度变化时安装滚子链将可动链轮和电动滚筒链条安装到理想的高度，可以将喂纱装置的所有部件安装在理想的位置。图 15.安装所有进料器单元板检查农场操作，包括系统设置和信息收集方法International Research Journal of Applied and Basic Sciences 2014 Available online at ISSN 2251-838X / Vol, 8 (10):1715-1725Science Explorer PublicationsOptimization of Combine Harvesting, Threshing, and Separating Systems for Reducing Corn LossRoohollah Mohammad Sanabadi Aziz1 , Sherwin Amini21. Research Instructor, Jihad Institute of Engineering (Located at 16km of Old Road Karaj, Tehran, Iran.2. MS Student in Mechanization Engineering, KhouzestanRamin Agriculture and Natural ResourcesUniversity, Khouzestan, Iran.Corresponding Author email: rohollahmohammadABSTRACT: Harvesting corn with a combine harvester leads to a certain degree of loss and thus reduces profits; although this loss cannot be fully eliminated, it can be controlled to areasonable degree. Preparing the combine for harvesting corn is a process involving the replacement of the harvest head and the concave and also the placement of cover plates on the threshing drum. A major obstacle in harvesting corn is the prevention of grain loss, which mostly occurs during the harvesting process at the combine head (when separating corn cobs from the stalks) and at the threshing drum and the concave (because of the corncobs breaking). The present research was conducted in a 400 acres farm property of the Seed and Plant Improvement Institute, Maize and Forage Crops Research Department, with prerequisites being a threshing drum speed of 750rpm and a crop moisture content of 11.6% on dry basis. The crop yielded and the amount of grain loss measured indicated that, when conventional heads exerting vertical force for separating the stalks are used, the degree of grain loss during harvesting becomes excessive; these heads cause a great amount of crop loss. Results of the present study were manifested on the combine cutter bars; therefore, for reducing harvest loss occurring at the combine header, headers made in Iran should be significantly modified. The first step taken in this respect was to design and implement necessary modifications to the two main parts of the machine, i.e. the “corn head” and the “feeder unit”.Keywords: Corn Combine, Reducing Harvest Loss, Combine Header Modification, Threshing Drum and Concave, Feeder UnitINTRODUCTIONThe increasing population of the world is faced withshortageof food and thus needs to expand its production of high yielding crops such as corn in order to overcome it. In terms of the global area under cultivation, corn comes third after wheat and rice. The rate of corn production has surpassed the rate of wheat and rice production over the last few years and is ranked first among agricultural products (Tajbakhsh, 1996). Mechanized harvesting of crops has long been a goal of farmers. The purpose of harvesting is the timely collection of grains and their separation from chaff and other waste parts with maximum quality and minimum amount of loss possible. In this regard, choosing the right method of harvesting and the appropriate equipment depends on the type of crop, the cultivation method and the climatic conditions (Sirvastava et al., 1990). The rate of corn loss when using a combine for harvesting corn depends on multiple factors such as the moisture content of the grain, ambient temperature, farm condition (stagnancy), combine condition (new or rusty) and the drivers level of experience. Together or separately, these factors can greatly increase grain loss. Knowledge of the aforementioned factors alongside the application of proper mechanisms of harvesting can reduce the rate of loss to a reasonable degree. Behrouzilar et al. (1995) conducted a study on the rate of crop loss for combine-harvested grains and cereals and planned to find out the global range of crop loss. They assessed factors contributing to crop loss in combine- harvested grains and cereals and concluded that in Iran, this rate is higher than the global standard, which is 4-5%. In their study on grain loss in commercial harvesting of oilseeds, Price et al. (1996) found out that the ideal grain loss can be around 2 to 5%. Under Irans normal climatic conditions, losses of 20-25% have also been recordedIntl. Res. J. Appl. Basic. Sci. Vol., 8 (10), 1715-1725, 20141716(Anonymous, 1997). As the combine feed rate increases, the overall loss rockets. The reason is that the straw walkers are overloaded (Navid et al., 2004). In another research, parameters such as speed of progression, peripheral speed of the threshing drum, the space between the cylinder and the sub-cylinder, size of sieve holes, fan speed and moisture content were measured (Rahama et al., 1999). Researchers also measured any form of loss occuring at the platform, the threshing drum and the separating and the cleaning system; they reported the mean loss to be 12%. In another research, the mean loss for combine harvests were reported to be 3.4% -1.5% of which pertained to platform loss (Bukhari et al., 1983). The use of a separating platform increases combine capacity by 50-100% due to the reduction in the amount of straw transferred to the separating and the cleaning systems (Tado et al., 1998). In order to prevent grain loss and removal of corn chaff at the combine header, the pulling sprocket and the rasp bars need to be adjusted closer to each other. The gathering chain speed and the pulling sprocketspeedalso need to be increased in low-performance farms so that the combine input increases and its maximum capacity does not drop (Hoffman, 2004). Adjusting the header to crop conditions is a major step in preventing harvest loss (Campbell automation, proper machine use and optimal use of machine technology increase efficiency, reduce costs and enhance production rates. To be self-sufficient in securing the countrys corn supply, all areas of the corn production process should be run with maximum efficiency. Since the purpose is to increase corn production and tpminimize its import (almost to zero), no loss should be toleratedespecially not at the harvesting stage, which can be subject to a high percentage of grain loss.MATERIALS AND METHODSThis project pursued to modify and optimize combine header systems and to achieve minimum grain loss in the production of corn; therefore, the first step was to purchase a combine corn head in order to study and analyze its systems. The source of corn loss occurring at the header was then identified along with other types of loss occurring at the system so as to identify their contributing mechanisms while taking all things into consideration and to then prepare for the standard testing and evaluation of the existing header. The next stage was to examine combine header operation mechanisms and to modify them according to the demonstrated causes of loss occurring in the combine for minimizing purposes. The final step was to conduct a trial run of the modified combine header on the farm so as to examine its degree of grain loss post modification and to compare it against its previous state.Examining combine headerThe examined system was a 4-rowcorn head that could be installed on John Deere 955 Combine Harvester. This head is designed to separate corncobs from their stalk and to then feed them to the feeder unit. This head has4 rows set at a fixed 75 cm distances of one another. The main parts of the system are:a) The Frameb) The Power transmission systemc) The Harvester (corn cutter)d) Grain conveyorCorn Head Technical Specifications: Required power: 45 hpInput rotation: 600 rpm Number of rows: 4Harvest rate: 4 acres per 8 hours Weight: 1000 kgLength: 320 cmWidth: 280 cmHeight: 130 cmIntl. Res. J. Appl. Basic. Sci. Vol., 8 (10), 1715-1725, 20141717Figure 1. Overview of the corn headDesigning and proposing a proper mechanismAt this stage of the project, combine head mechanisms directly in contact with the crop and causing corn loss were first examined; then, based on the envisioned mechanisms, necessary modifications were made taking into account the functioning of the examined head components.Examining the combine headers feeder unit mechanismAs the combine harvester rides along the farm, the crop is fed to the feeder unit that then separates the cobs from their stalks. The feeder unit is responsible for the separating process; the movable parts of this unit derive their power from the mechanisms embedded gearbox. The parts enabling the separating and feeding of the corncobs are as below:Figure 2. Feeder unit mechanismU-shaped frame Cutter barsChain conveyor mechanism Chain tightener spring mechanism SprocketStraw walker GearboxFeeder mechanism (of existing combine headers)The feeder unit parts can be divided into two general categories of fixed parts and movable parts. The fixed parts include the U-shaped frame, the chain tightener spring, the cutter bars and the straw walker. The movable parts include the chain, the roller chain and the sprocket wheel. The power transmission system transmits power to the gearbox.Intl. Res. J. Appl. Basic. Sci. Vol., 8 (10), 1715-1725, 20141718Separating corncobs from the stalksThe corn head was designed by the factory in such a way as to form an attack angle with the farm when installed on the combine. The examined 4-row corn head also boasts three head covers that direct the corn stalks into the feeder unit while the combine harvester is moving through the field. Thus as the combine moves along the corn fields, corn stalks flow into the feeder unit. Parts directly involved in separating the corncobs from the stalks are the cutter bars (1) and the sprockets (2). As formerly mentioned, the cutter bars are placed on the U-shaped frame and two sprockets are also placed under the frame. The sprockets rotate against each other by means of their movable gear. The direction in which the sprockets rotate is devised in a way that an opposite rotation against each sprocket draws the stalks down (into the cutting bars). Given the conical shape of the sprockets, upon flowing into the feeder unit, the corn stalks do not immediately contact the sprockets; rather, they only gradually get exposed to the sprockets while moving through the feeder unit. The sprockets are installed in such a way as to draw the corn stalks down into the cutting bars. The space between the cutter bars is adjusted based on the dimensions and size of the harvested corncobs in such a way that the cobs cannot freely move through these spaces; in addition, since the sprockets blades overlap each other, the stalk continues to be drawn and the corncob is thus separated from its stalk. The cob breaks along its own axis at its end so that the corncob ears also loosen from the stalk.Figure 3. System for separating the cobs from the stalkConveying corn cobs to the feeder unitOnce separated from the stalk, the cobs should be conveyed to the threshing drum and the concave. This moving is carried out through three conveyors, two of which are installed on the combine header and one inside the combine harvester. Once the crops have been fully separated, they should be conveyed to the header augerso as to be gathered; they are then sent through the conveyor. The first conveyor (“grain conveyor”) is installed in the feeder unit. Machine parts directly involved in conveying the corncobs to the feeder unit include:Conveyor chain Motor roller chain Moving roller chainBushings placed on the chainFigure 4. Grain conveyorProposed mechanism for reducing corn lossIntl. Res. J. Appl. Basic. Sci. Vol., 8 (10), 1715-1725, 20141719As previously mentioned, the stalks get pulled down by the sprockets in the corn head; the corncobs, too, are rapidly being pulled downso that they get stuck between the cutter bars and get separated from the stalk.Figure 5. Proposed mechanism for reducing corn lossIn existing heads, when the cobs are being separated from the stalk, the cobs are pulled along their longitudinal axis, which exerts a vertical force on the base of the cobs;as a result, the cobs get broken from the base and the corns also get separated from the cobs.Figure 6. Cobs breaking along their longitudinal axisOur proposed mechanism aims to reduce loss of corns when the corncobs are being separated from the stalks. Since the main reason for the separation of the corns from the corncobs was the vertical force exerted along the longitudinal axis of the cobs, this study aims to modify the current mechanism and instead achieve one that minimizes the force exerted on the cobs. Once necessary modifications are made to the mechanism separating the cobs from their stalks, direction of the pulling force and thus the separation deviates from along the cobs axis so that separating the cobs from the stalks can be easily achieved without unnecessary loss-provoking shocks or vibrations. The latter can be accomplished by creating variance between the cutting bars altitudes. These modifications have three advantages:Due to the exertion of force at a more suitable angle, separating the cobs from the stalks is easier and requires less power and force. The reduction in the collision force is highly effective in preventing loss of the corns during the stage where the cobs are being separated from the stalks.Direction of force exerted on the grains has changedyet another modification contributing to the reduction in corn loss.Stalks are broken right at their junction with the cobs (point A); as a result, the cob ears are also separated from the cobs since they are joint to the stalks too. Therefore, if, during the separating stage, the stalk is broken right at its junction with the cobs, all the cob ears will break as well. It is clear that reducing waste input to the combine harvester (particularly to the threshing drum and the concave) positively affects quality of the operation. Creating a variance in the cutting bars altitudes changes the direction of F force exerted on the end point of the cob so that F is no longer exerted along the axis of the cob; consequently, the force exerted in the direction of the axis becomes part of F.Proposed mechanism for reducing lossIntl. Res. J. Appl. Basic. Sci. Vol., 8 (10), 1715-1725, 20141720As previously mentioned, reducing the amount of loss can be achieved by decreasing the axial tensile force to the minimum effective degree possible, which means that a variance should be created between the cutter bars altitudes in the feeder unit. To create this variance, filler plates are installed underneath a cutter bar in order to place it higher above the other cutter bar.Figure 7. Filler platesIt should be noted that the chain conveyor mechanism and the chain tightener spring mechanism are also positioned on the cutter bars. Moving the position of the cutter bars repositions these mechanisms as well; therefore, changes that should be made to all three parts are described:Creating variance in the altitude of a cutter barThe intended variance to be createdbetween the cutter bars altitudes for testing the reduced rate of corn loss was 10 and 15mm; the filler plates used for creating this altitude variance had a diameter of 5mm.Figure 8. The feeder unit frameThe corn head has 4 rows, that is, four separating mechanisms; one mechanism received 10mm of altitude variance, another one received 15mm of it, and the other mechanisms remained intact so that the amount of loss in each harvesting path could be examined and the effect of the amount of altitude variance on the degree of grain loss could be measured.Figure 9. Cutter barsRepositioning the chain tightener spring mechanismIntl. Res. J. Appl. Basic. Sci. Vol., 8 (10), 1715-1725, 20141721The chain tightener spring is placed on top of the cutter bars; changing the position of the cutter bars thus repositions this spring as well. The chain tightener spring can only be moved vertically; therefore, the mechanism itself will not be modified, instead, the screws mounting the mechanism on the U-shaped frame will only be placed 20mm higher than their previous position.Figure 10. Chain tightener spring mechanismGrain conveyor chain mechanism installation and set upThe conveyor chain mechanism is also placed on top of the cutter bars; therefore, changing the position of the cutter bars repositions this mechanism as well. As previously mentioned, the grain conveyor chain mechanism consists of two roller chains (a motor roller chain and a movable roller chain) and a chain, and each feeder unit contains two grain conveyor mechanisms. The movable roller chain is placed on the L-shaped tightener spring mechanism; moving the latter results in the modification and repositioning of the movable roller chain. The grain conveyors motor roller chain is positioned along the axis of the movable gear of the gearbox conveyor chain. Given that the motor roller chain should also be repositioned along the aforementioned axis once the position of the cutter bars changes, the length of the axis should be adjusted and suitable filler gaskets should be designed for the accurate adjustment of the space.Figure 11. Mounting the chain mechanism on the feeder unit frameAs previously mentioned, modifications are only made totwoout of the four units existing in the feeder unit; in one of the units, one cutter bar is placed 10mm higher above the adjacent cutter bar and, in another unit, one other cutter bar is placed 15mm higher above the adjacent one. Therefore, the length of the axis of the gearbox conveyor chains movable gear should be increased by 20mm.Figure 1
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