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电缆 阻力 收放器

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电缆恒阻力收放器机械设计带图纸,电缆,阻力,收放器

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本科毕业设计(论文) 电 缆 恒 阻 力 收 放 器作 者 姓 名 高亮 专 业 机械08-2 指导教师姓名 范维华 专业技术职务 2012 年 06 月 06 日目 录摘 要3 第一章 绪论51.1电缆恒阻力收放装置的发展现状 51.2对选题的研究51.3课题条件51.4总体设计方案框架5 第二章 动力机构设计52.1动力系统选择依据52.2动力计算62.3动力选型6 第三章 传动系统设计73.1常见机构的特点和应用73.2传动机构的确定93.3带传动计算9 第四章 离合器的选择设计124.1恒定距离合器设计计算124.1.1选型124.1.2恒定距电磁离合器的动作特性124.1.3离合器的计算转矩124.1.4离合器的外径124.1.5离合器的压紧力124.1.6线圈槽高度134.1.7磁轭底部厚度134.1.8衔铁厚度13第五章 轴的设计计算135.1 轴的设计1551.1 最小直径155.1.2 轴上各零件的布置方案155.2 轴的强度校核165.3轴承的使用寿命校核185.3.1 轴轴承的寿命校核185.3.2 轴承的寿命校核19 第六章 我国电力施工发展现状20总 结21参考文献22致 谢23摘 要在工业生产还是我们的日常生活中电缆线都有着重要的作用，给我们带来很多的利益。随着现代电力施工的发展，电缆线盘托运及展放需要的自动化程度不断提高，电缆收放装置是现代电力施工系统的重要设备之一，其主要功能是将电缆线盘进行运送和展放。电缆恒阻力收放器对整个电力施工系统的可靠安装将起到重要的作用。关键词：电缆收放 电缆线盘232012届山东轻工业学院本科毕业设计（论文）AbstractIn the industrial production and our daily life cable has an important role, give us a lot of benefits. With the development of modern electric power construction development, cable reel checked and show need to continuously improve the degree of automation, retractable cable device of modern electric power construction system is one of the important equipment, its main function is to the cable reel for laying. Constant resistance cable deploying and retracting device for the electric power construction system and reliable installation will play an important role.Key words: cable reel retraction ;cable reel第一章 绪论1.1电缆恒阻力收放装置的发展现状在许多大型机械的维修行业中，有时要进行一些线类物件的收放，目前普遍的做法是用机械式的电缆恒阻力收放，有的地方人工倒送的方式，费时，费力，而且对工作人员存在安全隐患。即使有的地方使用电缆恒阻力收放器，但它是纯机械的，用起来很费力。1.2对选题的研究下面简要的介绍一下电缆恒阻力收放器，它采用电动机作为收放动力。电动由于减速和回转运动变往复运动机构，该机构适用于无污染，有电就可以工作，操作简单方便，在工作场合只需要接通电源即可工作，而工作场合在各个大楼区域，很容易找到电源。是以后发展的方向，只有有好的工具才能在日常中更好的维护机器。在今后的高科技时代，高科技的维修工具是不可少的。电缆恒阻力收放器的改革和创新也是时代发展的必然。1.3课题条件适用对象：电缆线拉力：25N-30N转速：30r/min1.4总体设计方案框架根据本课题的研究是收放电缆线。根据实际需求拟采取如下：动力选择：电动机（带减速器）传动形式：带条传动机架机构：钢板，型材焊接 第二章 动力机构设计2.1动力系统选择依据驱动机构主要有液压驱动、气动驱动、电动驱动和机械驱动等形式。液压驱动具有体积小、出力大、控制性能好、动作平稳等特点，它利用油缸、马达加上齿轮、齿条实现直线运动；利用摆动油缸、马达与减速器、油缸与齿条、齿轮或链条、链轮等实现回转运动。液压驱动具有润滑性能好、寿命长的特点，结构紧凑，刚性好。定位精度高，克实现任意位置开停。有很多专业机械手能直接利用主机的液压系统。但缺点是需要配备压力源，系统复杂成本较高。气动驱动结构简单、造价低廉。气源方便，所需的压缩气源一般工厂都有，并且无污染，一般采用的压力0.4-0.6MPa,最高可达1MPa。缺点是出力小，体积大。由于空气的可压缩性大，很难实现中间位置的停止，只能用于点位控制，而且润滑性较差，气压系统容易生锈。机械式用于简单的场合。电动由于减速和回转运动变往复运动机构，该机构适用于无污染，有电就可以工作，操作简单方便，在工作场合只需要接通电源即可工作，而工作场合在各个大楼区域，很容易找到电源。 综合以上叙述，将选用最后一种电动机作为本课题的动力来源。2.2动力计算由于本设计卷筒速度v=3m/min，n=30r/min机构功率为：2.3动力选型由上面计算结果知道需要输出转速很低，根据机构需要选择摆线针轮减速器，其主要特点是传动比大，一级转速时传动比在11-87，两极转速时传动比范围在20128。由于在传动过程中为多齿齿合，所以对过载和冲击有较强的承受能力，传动平稳，可靠；由于采用了行星摆线传动结构，所以其结构紧凑、体积小、重量轻，在功率相同条件下，其质量是其它减速器的一半，由于摆线齿轮、针齿销、轴销和轴套都是由轴承钢制造，工作中又的有滚动摩擦，因此大大加强了个零件的机械性能并保证使用寿命，提高了传动效率。 由于转速需30r/min ，输出功率需要大于0.0015KW，表15-2-119选择二级直连型XWED8175B型，传动比50，输入转速1500r/min,输出转速30r/min，额定转矩2750N.M,额定功率为1.1KW(考虑超载及摩擦等其他不可意料的因素，这个值尽量取大一些).其机构尺寸如图（JB/T298-1994）图2-1 二级直连型XWED8175B型电动机（带减速器的）第三章 传动系统设计3.1常见机构的特点和应用类型特点应用连杆机构结构简单，制造容易，工作可靠，传动距离较远，传递载荷较大，可实现急回运动规律，但不易获得匀速运动或其他任意运动规律，传动不平稳，冲击与振动较大用于从动件行程较大或承受重载的工作场合，可以实现移动、摆动等复杂的运动规律或运动轨迹。凸轮机构结构紧凑，工作可靠，调整方便，可获得任意运动规律，但动载荷较大，传动效率较低用于从动件行程较小和载荷不大以及要求特定运动规律的场合。非圆齿轮机构结构简单，工作可靠，从动件可实现任意转动规律，但齿轮制造较困难用于从动件作连续转动和要求有特殊运动规律的场合。槽轮间歇机构结构简单，从动件转位较平稳，而且可实现任意等时的单向间歇转动，但当拨盘转速较高时，动载荷较大常用作自动转位机构，特别适用于转位角度在45以上的低速传动。凸轮式间歇机构结构较简单，传动平稳，动载荷较小，从动件可实现任何预期的单向间歇转动，但凸轮制造困难用作高速分度机构或自动转位机构。不完全齿轮机构结构简单，制造容易，从动件可实现较大范围的单向间歇传动，但啮合开始和终止时有冲击，传动不平稳多用作轻工机械的间歇传动机构螺旋机构传动平稳无噪声，减速比大；可实现转动与直线移动，传动平稳无噪声，互换；滑动螺旋可做成自锁螺旋机构；工作速度一般很低，只适用于小功率传动多用于要求微动或增力的场合，如机床夹具以及仪器、仪表，还用于将螺母的回转运动转变为螺杆的直线运动的装置。摩擦轮机构有过载保护作用；轴和轴承受力较大，工作表面有滑动，而且磨损较快；高速传动时寿命较低用于仪器及手动装置以传递回转运动。圆柱齿轮机构载荷和速度的许用范围大，传动比恒定，外廓尺寸小，工作可靠，效率高；制造和安装精度要求较高，精度低时传动噪声较大，无过载保护作用；斜齿圆柱齿轮机构运动平稳，承载能力强，但在传动中会产生轴向力，在使用时必须安装推力轴承或角接触轴承广泛应用于各种传动系统，传递回转运动，实现减速或增速、变速以及换向等。齿轮齿条机构结构简单，成本低，传动效率高，易于实现较长的运动行程；当运动速度较高或为提高运动平稳性时，可采用斜齿或人字齿条机构广泛应用于各种机器的传动系统，变速操纵装置，自动机的输送、转向、进给机构以及直动与转动的运动转换装置圆锥齿轮机构用来传递两相交轴的运动；直齿圆锥齿轮传递的圆周速度较低，曲齿用于圆周速度较高的场合用于减速、转换轴线方向以及反向的场合，如汽车、拖拉机、机床等。螺旋齿轮机构常用于传递既不平行又不相交的两轴之间的运动，但其齿面间为点啮合，且沿齿高和齿长方向均有滑动，容易磨损，因此只宜用于轻载传动用于传递空间交错轴之间的运动。蜗轮蜗杆机构传动平稳无噪声，结构紧凑，传动比大，可做成自锁蜗杆；自锁蜗杆传动的效率很低，低速传动时磨损严重，中高速传动的蜗轮齿圈需贵重的减摩材料(如青铜)，制造精度要求较高，刀具费用昂贵用于大传动比减速装置(但功率不宜过大)、增速装置、分度机构、起重装置、微调进给装置、省力的传动装置行星齿轮机构传动比大，结构紧凑，工作可靠，制造和安装精度要求高，其他特点同普通齿轮传动；主要有渐开线齿轮、摆线针轮、谐波齿轮3种齿形的行星传动常作为大速比的减速装置、增速装置、变速装置，还可实现运动的合成与分解。带传动机构轴间距离较大，工作平稳无噪声，能缓冲吸振，摩擦式带传动有过载保护作用；结构简单，安装要求不高，外廓尺寸较大；摩擦式带传动有弹性滑动，不能用于分度系统；摩擦易起电，不宜用于易燃易爆的场合；轴和轴承受力较大，传动带寿命较短用于传递较远距离的两轴的回转运动或动力。链传动机构轴向距离较大，平均传动比为常数，链条元件间形成的油膜有吸振能力，对恶劣环境有较强的适应能力，工作可靠，轴上载荷较小；瞬时运转速度不均匀，高速时不如带传动平稳；链条工作时因磨损伸长后容易引起共振，一般需增设张紧和减振装置用于传递较远距离的两轴的回转运动或动力。3.2传动机构的确定根据上述表格和件，距离较远，属于长距离输送。初步选择带传动机构和链条传动机构。带传动机构运行平稳，安装要求不高。最终确定带传动作为本的传动机构。3.3带传动计算1）确定设计功率公式：Pd=KAP式中：KA工作情况系数；P所传递的功率KW；由设计资料得KA=1.2得Pd =1.3kw2）选择V带的型号普通V带的型号根据传动设计功率Pd和小带轮的转速n1选取：已知：Pd =1.32kw n=1440r/min查机械设计手册应选用B型带。3）确定带轮基准直径dd1，dd2并验算带速由资料GB/T13575.1-92中选取dd1=140则：dd2= dd1=n1dd1/n2=150得dd1 =140 dd2=150验算带速v v=v1=d1n1/60000m/s =3.14X1460dd1/60000=18.6m/s25m/s带速在允许范围之内。4）验算传动比误差转动比：i= dd2/dd1=150/140 =0.97原传动比：i= dd1=n2/n1=1460/1440 =0.96=（0.97-0.96）/0.97=+2.25%在允许误差范围内。5）确定中心距a及带的基准长度Ld可设定中心距：ao=500mm则可以计算带长Ld0由公式：Ld02a0+（dd1+ dd2）+ 102 mm得Ld0=2X500+1.57（140+150）+102/6000=1450mm由资料选取Ld0=500mm确定实际的中心距a：由公式：aa0+ mm得：a=500+100/2=550mm中心距调整范围amax=a+003Ld=550+0.03X3550=1656.5mmamin=a-0015Ld=550-0.015X3550=1496.75mm6）验算小带轮包角a1由a1=180-573=180-573X0.01=175.3120所以合适。7）确定V带的根数Z由公式：Z= = 根查资料可得P0=2.83kw KA =0.99 KL=1.30 带入数据得Z13.2/（3X1.5）=2.96取Z=3根8）确定带的初拉力F0由公式：F0=500 +qv2N其中查表得q=0.17kg/m带入数据得：F0=500X =256N 9）计算作用在轴上的压力Fz由公式：Fz2ZF0sina/2得：Fz=2X3X sin180/22136N第四章 离合器的选择设计4.1恒定距离合器设计计算4.1.1选型为满足工作环境的需要，在系统中我选择恒定距离合器，因为恒定距离合器有外形尺寸小，传递转矩大，无空转转矩，无摩擦发热，无磨损，不需调节，传动比恒定无滑差，使用寿命长，脱开快，干、湿两用的特点。（电源为12v直流电）4.1.2恒定距电磁离合器的动作特性通电后，当激磁电流按指数曲线上升时，由于衔铁被吸引，线圈中电感增大，引起电流第一次短时间下降，以后还会由于衔铁吸引后尚不能起动负载转矩，出现牙间嵌合、脱开和再嵌合的滑跳现象，致使电流发生多次跳动，直到能带动负载转矩时才趋向稳定。对于静态接合，起动时间的长短主要与衔铁吸引时间有关，而对动态起动，则与相对转速、负载特性、负载的增加情况以及牙的相对位置等因素有关。离合器的脱开时间就是从切断激磁电流开始到牙完全脱开嵌合，传递力矩消失所经历的时间，此时电流也按指数曲线衰减。4.1.3离合器的计算转矩 式中 T-离合器传递的理论转矩，它包括工作转矩和起动的惯性转矩 T=2168（Nm）； K-工作情况系数 K=1.5所以 1.5 2168=3252（Nm）4.1.4离合器的外径 =1334.1.5离合器的压紧力 Q式中 -牙形角， = -摩擦角， = -牙的平均直径 -衔铁摩擦面的摩擦系数 -衔铁导向孔直径 -弹簧推力，=404.1.6线圈槽高度 =20mm式中 -线圈槽高度比， =5 -传热系数，=11 -填充系数， =0.6 -电阻系数，=0.0174.1.7磁轭底部厚度 =4mm4.1.8衔铁厚度 =8mm 一般取余量 =4第五章 轴的设计计算5.1 轴的设计51.1 最小直径 D A0= 105 =34.8mm (4-1-1)A0的值取自机械设计表153，因为轴上有两个键槽，故将轴的最小直径提高至原来的1.0倍。圆整后 dmin =38mm.5.1.2 轴上各零件的布置方案：主动轮轴上安装着主动轮，以及一对深沟球轴承6220。根据后面的应力计算分析可知轴的材料选为45号钢，调质处理。根据最小轴径，以及轴承的内径、主动轮轮轴的内径确定轴上各段的径向尺寸，根据轴承座长度度及轴承宽度确定轴的总长度。各段长度由安装在轴上的零件尺寸确定。轴上的零件要有两个方向的定位，一个是轴向定位，一个是周向定位。主动轮的周向定位采用键联结，轴向定位由轴承端盖和紧钉螺钉完成。轴通常是在变应力条件下工作的，轴的截面尺寸发生突变处要产生应力集中，轴的疲劳破坏往往在此处发生。为了提高轴的疲劳强度，应尽量减少应力集中源和降低应力集中的程度。为此，轴肩处应采用较大的过渡圆角半径来降低应力集中。但对定位轴肩，还必须保证零件得到可靠的定位。图5-1 轴上零件定位图根据定位图可以得到轴的零件图如下（图5-2）图5-2 轴的零件图5.2 轴的强度校核：图 5.2 轴受力简图根据力平衡条件列平衡方程 630+F2=F1， (4-2-1) F215063049 （4-2-2）由上述方程组得 F1=924N ,F2=294N由上述值可画出剪力图，如下图：图5.3 剪力图由上图得AB段弯矩为 Mab=294105=30870N.mm=30.87N.m （4-2-3） BC段弯矩为 Mbc=63049=30870N.mm=30.87N.m （4-2-4）因为30.87-30.87=0N.m所以可得弯矩图B点为值为30.87N.m弯矩图如下：图5.4 弯矩图扭矩为 T=We=9549P/n=95490.1364 =324.6N.m （4-2-5）扭矩图为图5.5 弯矩图由此可见轴的危险截面在B点 MB = 30.87N.m TB = 324.6N.m B = （4-2-6） = 26.54Mpa45号钢的抗拉强度极限为：600Mpa ；屈服极限：355Mpa（见机械设计手册表27） Bs （4-2-7）故轴的尺寸结构满足强度要求。5.3轴承的使用寿命校核5.3.1 轴轴承的寿命校核主动轮轴轴承中径向力最大为0.977KN。 P = fp Fr =1.20.977KN =1.17KN （4-3-1）fp的取值见机械设计表1366210滚动轴承的基本额定动载荷C=35KNC的取值见机械设计课程设计手册表61。 Lh = (4-3-2） = =1.11108h5.3.2 轴承的寿命校核 P = fp Fr =1.20.924KN = 1.1KN (4-3-3)Lh = （4-3-4） = = 1.34108h移苗机每天工作10小时，每年工作600小时，设计轴承使用寿命为6年。 Lh = 6006 3.6103 h （4-3-5） Lh Lh ，满足设计要求。 第六章 我国电力施工发展现状首先介绍一下传统电力施工中的旁路作业法，旁路作业法是先引入旁路电缆对工作区域内的负荷进行临时供电，再将工作区域内的电气设备停电后进行检修，期间可以保证对用户的不间断供电，实现不停电检修。旁路带电检修更换配电线路，其主要工作量在于运输旁路电缆，架设旁路，目前架空旁路电缆的运输多采用普通载货汽车，电缆卷盘为单体绕放结构，施工时，将电缆卷盘运输到施工现场，采用吊车或其他起吊工具，人工收放电缆，完成架空线路的铺设，此种作业方法需要多人配合作业，电缆运送车辆受道路交通限制，往往深夜提前运至施工现场，电缆在运送过程中难免磕碰损伤，且作业劳动强度较大，极大的限制了旁路作业设备在应急抢修和架空线路不停电工作的应用。电缆车是电力施工中电缆线盘托运及电缆的展放的必备工具。本设计的电缆车弥补了传统旁路作业法的缺点和不足，首先电缆车通过其中装置（选用3.2t螺纹千斤顶）使电缆脱离地面，同时电缆架设在缆车的轮轴之上，可通过手动摇杆使电缆转动实现电缆的收卷和展放。位于电缆车前方的牵引轮胎，可任意改变角度，移动灵活。电缆车配有减震装置大大增强了稳定性能。这些设计和改进有利于电缆车在狭窄的场地和野外路面不平地带作业，极大的减小了劳动工作强度，使电缆的野外铺设机动灵活性显著提高。2012届山东轻工业学院本科毕业设计（论文）总 结时间过的很快，短短的几个月，一转眼就过去了，而我的毕业设计“电缆恒阻力收放器的设计”在老师和同学的帮助和指导下终于完成。在整个设计过程中，做很多的工作并不是一帆风顺，刚开始对“电缆恒阻力收放器”是一个模糊的概念，起初还真的有点无从下手的感觉。但是，经过公司的实习过程中，让我真的知道了是怎样工作的，它的每一个动作是怎样执行的。特别是前期工作对资料的查询，但一段时间后还是没有什么进展的，当时心里有点急了，这样下去什么时候才能够完成呢，于是就不断的向同学以及师兄请教，由于还有很多的工作要做，还需要查很多的资料，于是去图书馆还有向同学借有关的书籍等等。对于CAD画图方面，由于以前没有认真的学习，所以就用一段时间来学习CAD,开始画的并不是很理想，经过老师的反复指导和监督下终于把相应的图纸画出来了。毕业设计是一个不断学习的过程，从最初到结束，让我真正知道理论很实际的重要性，要做好一件事情要考虑的因素有很多，必须合理的安排好设计时间。学校是一个小社会，出到学校外面工作是一个复杂的社会，毕业设计就是我们接触外面的世界的一个转折点。总之，通过毕业设计,我深刻体会到要做好一个完整的事情，需要有系统的思维方式和方法，对待要解决的问题，要耐心、要善于运用已有的资源来充实自己。同时我也深刻的认识到，在对待一个新事物时，一定要从整体考虑，完成一步之后再作下一步，这样才能更加有效 。参考文献参考文献1. 吴宗泽主编.机械设计与课程设计. 高等教育出版社18982. 黄华梁主编.机械设计基础第二版.中央广播电视大学出版社.19903. 吴宗泽主编.机械设计禁忌500例.机械工业出版社.19884. 吴宗泽主编.机械设计实用手册.化学工业出版社.19905. 成大先主编. 机械设计手册. 北京：化学工业出版社.20046. 花国梁主编. 互换性与测量技术基础. 北京：北京理工大学出版社.19907. 熊文修主编.机械零件.高等教育出版社.19978. 罗圣国主编.机械设计课程设计手册第二版.高等教育出版社 19989. 郑树森主编.机械零件设计手册.哈尔滨工业大学.199810. 包清彬主编.新型连续式洗米机.四川工业学院学报.2001，2：（3）293711. 无锡轻工业大学，天津轻工业学院合编.食品工厂机械与设备.北京：中国轻工业出版社，199712. 胡勇克主编.螺旋输送器的原理与设计.南昌大学机械工程学院.2000,12: (4) 303313. 编辑委员会编.运输机械设计选用手册.化学工业出版社下册199214. 梁庚煌主编. 运输机械设计选用手册下册.教育出版社.199015. 编写组编. 电机修理实用技术数据手册. 教育出版社.199016. 蕃臣林主编.电机检修实用手册. 教育出版社.1992致 谢四年的艰苦跋涉，几个月的精心准备，毕业论文终于到了划句号的时候，心头照例该如释重负，但写作过程中常常出现的辗转反侧和力不从心之感却挥之不去。论文写作的过程并不轻松，工作的压力时时袭扰，知识的积累尚欠火候，于是，我只能一次次埋头于图书馆中，一次次在深夜奋笔疾书。第一次花费如此长的时间和如此多的精力，完成一篇具有一定学术价值的论文，其中的艰辛与困难难以诉说，但曲终幕落后留下的滋味，值得我一生慢慢品尝。敲完最后一个字符，重新从头细细阅读早已不陌生的文字，我感触颇多。虽然其中没有什么值得特别炫耀的成果，但对我而言，是宝贵的。它是无数教诲、关爱和帮助的结果。我要感谢我的指导教师范维华老师。老师虽身负教学、科研重任，仍抽出时间，不时召集我和同门以督责课业，从初稿到定稿，不厌其烦，一审再审，大到篇章布局的偏颇，小到语句格式的瑕疵，都一一予以指出。是他传授给我方方面面的知识，拓宽了我的知识面，培养了我的功底，对论文的完成不无裨益。我还要感谢学院所有教过我的老师，是你们让我成熟成长；感谢学院的各位工作人员，他细致的工作使我和同学们的学习和生活井然有序。谨向我的父母和家人表示诚挚的谢意。他们是我生命中永远的依靠和支持，他们无微不至的关怀，是我前进的动力；他们的殷殷希望，激发我不断前行。没有他们就没有我，我的点滴成就都来自他们。让我依依不舍的还有各位学友、同门和室友。在我需要帮助的时候他们伸出温暖的双手，鼎立襄助。能和他们相遇、相交、相知是人生的一大幸事。本论文的完成远非终点，文中的不足和浅显之处则是我新的征程上一个个新的起点。我将继续前行！山东轻工业学院中英文翻译院系名称 机械工程学院 学生姓名 高亮 专业班级 机械设计制造及其自动化08-2 指导教师 范维华 二一二年六月一日Farm Mechanization in Sri LankaM.W.N.DHARMAWARDENESri Lanka Sugarcane Research Institute, Sri LankaABSTRACT The mechanization of farm power is becoming extremely important day by day for the survival, efficiency of all field and plantation crops of the country. Sugarcane crop grown in the dry zone is no exception. In fact in these areas the available manpower is low due to low population densities and harsh climatic conditions and remoteness of locations from major cities. Furthermore, labourer manual work get easily tired while working in the dry zone compared to the hills due to higher temperatures, harder soils, insolation and dry desiccating winds. In addition, cane fields tend to have a high population of poisonous snakes, which also make worker to be careful and slow in the cane fields. Thus timely agricultural operations get neglected causing crop losses while labour wages keep rising day bydayespeciallyduring planting, weeding and harvesting/loading periods of sugarcane growing. Analysis of the cost components of sugarcane cultivation shows that harvesting of loading of cane comprise 35% of the costs followedbylandpreparation(21%), planting(16%),weeding(l0%),fertilizer application(10%) and irrigation(8%).It is evident that harvesting and loading of cane isthehighestcostcomponentinsugarcanecultivation,whileweeding,fertilizerapplication ,stubble shaving, earthing up, off baring in the ratoons are neglected by small land holder farmers as manual methods are labour intensive leading to considerable losses in crop production. Thus, small holder sugarcane farm mechanization to improve the productivity and ease strain on human labour has become crucial in order to improve sugarcane productivity in Sri Lanka. Some of the smallholder farm tools and implements developed by the Sugarcane Research Institute which can be powered by a two-wheeled tractor such as the SRI tyne cultivator, Fertilizer applicator, Disc ratooner, Furrow opener, and the new design sugarcane harvesting knife。Key words : Sugarcane, farm mechanizations,Sri LankaINTRODUCTION Sugarcane growing for vacuum pan sugar production in Sri Lanka is largely carried out by small holder farmers. The extents of these small farms range from one to five hectares. Except for the initial land preparation carried out using conventional farm machinery,the rest of the operations from planting to harvesting, employmanualmethods either using family labourorhired labour.Analysis of cost of production of sugarcane in these small holder farms in Sri Lanka shows that highest cost component is for sugarcane harvesting and loading followed by land preparation, planting, weeding, fertilizer application and irrigation.Most of these operations when carriedoutmanually are labour intensive, time consuming and tiresome field work under hot tropical conditions. As a result, these often get neglected due to unavailability of labour for such heavy manual works. Furthermore, small holder farmers find it difficult to complete a given task within a specified period of time which affects both the sugarcane yields and its quality . It is often observed that productivity of manual workers decrease quickly within a few hours of working in the hot tropical sun, who then resorts to taking short breaks for rest leading to disruption of work. Thus in manual cultivation of sugarcane, much of the recommended practices such as timely weeding, fertilizer application, off baring, on barring, cutting cane in plush with the ground at harvesting, stubble shaving etc are neglected leading to poor stand of both in plant and ratoon cane especially when hired labour is used. Much absenteeism among hired labour is common in highland cultivation of crops in the dry zone. It is also observed that much of the youth population in farming areas tend to shy away from suchtraditional agriculture leading to much of rural urban drift. Thus it is realized that productivity improvements and sustainability of small holder farms are heavily dependent on introduction of appropriate level of mechanization.The following levels of mechanization could be recognized in small holder sugarcane fanning system in Sri Lanka: (a) traditional hand tool technology (b) improved hand tool technology (c) animal draught technology (d) mechanical power technology at the level of single axle tractors(power tillers) (e) mechanical power technology at the level of four-wheel TractorsIn practice, different sources of power are used in different parts of sugarcane growing areas. Edaphic conditions such as heavy soils often limit the effectiveness of the above first three options.Although, the use of last option namely the four-wheel tractor in each of the above operationsimproves he productivity and timely operations of. the said cultivation practices, unavailability of four wheeled tractors at the disposal of small holder farmers, small size of the land holdings and unfamiliarity of the farmers with four wheeled tractors, and the escalating cost of hire makes it unsuitable as the principal source of farm power for the traditional small holder farmer in Sri Lanka.On the other hand most of the small holder farmers are either familiar or own a single axle tractor (5 to 7 HP) as it is commonly used in lowland paddy cultivation. Furthermore, repairs and other services required for those power tillers are freely available in those areas. However, in Sri Lanka, there were no matching implements for these power tillers which could be used in highland cultivation of sugarcane. Some of the implements that were developed by the Sri Lanka Sugarcane.Single axle Tractor Implements Developed by SRI Tyne CultivatorThis implement is a new design of an agricultural implement, as an attachment to a two wheeled tractor, to mechanize the cultural practice of inter row cultivation or weeding the sugarcane fields (Fig. 2). The implement will enable the small holder farmer to weed his/her sugarcane plot effectively within a short duration of time whenever it is required and convenient to him as he does not require additional hands to be hired for this purpose.Fig. 2. SRI Tyne cultivator(1. Main Frame; 2. Hitch Unit; 3 Shank; 4 Shoe; 5 Brace; 6 Bracket; 7 Bolt Holes; 8 Shoe Fixing Bolts)Inter row cultivation is one of the important cultural practices crucial to control weed populations in sugarcane plots especially when there are no inter crops. These have to be pulled out either manually or use chemical herbicides. This cultural practice reduces the competition between weeds and the sugarcane for nutrients, soil moisture and sunlight. Weeds are also known to harbour insect pests of sugarcane. In Sri Lanka, 10 -13% sugarcane crop losses due to weed competition is common but it may rise up to even 30% during rainy periods。Animal drawn implementsThe three tyne cultivator was developed by the SRI, having a design similar to that of the Indian make. The implement consists of a tool bar to accommodate three tines fixed to a wooden beam, which is tied to the animal hamess. However this has following limitations: i. Row spacing of 1.37m in sugarcane farming used at present tend to damage the crop as the animal moves up the inter row. ii. Scarcity of trained draft animalsPower tiller mounted rotovatorThe rotovator used for pulverizing paddy soils is also used for inter row cultivation by smallholder sugarcane farmers. Its disadvantages are i. It causes too much pulverization of the soil destroying the soil structure. ii. Costs of rotovator and its running costs are high. iii. Frequent replacements of cutting blades are required due to high wear and tear.Four wheeled tractor & implementsThe nine spring tyne cultivator with three middle tines removed is used for inter row cultivation in cane fields. However the implement and the four wheeled tractor are not generally available for small holders. The development of the SRI tyne cultivator which could be coupled to two wheel tractor as its prime mover has given the small holder farmer a cost effective method and has made him independent of hire manual labour as far as the inter row weeding operation is concerned. The implement shown in Fig 2 consists of(a) a frame, (b) a hitch unit and (c) five tynes with replaceable shoes.The main frame is trapezoidal in shape. It consists of three box section cross members for mounting of tines. All the three cross members are provided with a number of bolt holes to enable lateral spacing adjustments between tines. The hitch unit enables the implement to be attached to the two-wheeled tractor. Four bolts are provided in the coupling bracket, two for mounting purposes and the others for proper alignment. A brace is bolted between the hitch unit and the main frame. It has number of bolt holes for adjusting the mounting angle ofimplement to the power unit for easy handling and better performance of the cultivator. The implement has a number of tines with replaceable shoes of different shapes. Each tyne has a shank, replaceable shoe of different shape to suit different soil conditions and a bracket with two bolts. The lower end of the shank is curved and in the curved end, a bolt hole is provided for mounting the shoe. Replaceable shoe has a bolt to enable it to be attached to the lower end of the shank. The shoes can be of different shapes to suit different soils and their conditions. A bracket with bolts is provided for fixing the tyne to the box section of the frame. The implement has provisions for adjustments of lateral spacing between tines, by changing the position of the tines brackets and fixing them in the bolt holes provided in the box section of the frame. The ground clearance of the implement is adjustable by sliding the tyne in the bracket. The brace is provided with a number ofbolt holes for adjusting the mounting angle of the implement to the tractor. It has the following dimensions: 540ram lenth, 690 mm width, 540mm height and 24 kg wight.Field tests have shown that the implement satisfactorily uproots weeds and cultivate soil with a field capacity of 0.1 hectare per hour. Thus one-hectare sugarcane plot in of Reddish Brown Earths soils(Alfisols) in the dry zone of Sri Lanka could be completed within 10 hours thus it replaces 20- 25 labour units required for the same operation by one operator for driving the two wheel tractor. It is cheaper by 42% to use the tyne cultivator than use manual labour for sugarcane weeding in the inter row. In addition to its cheapness, giving freedom to farmer to operate at his will, it cultivates soil increasing soil aeration and increasing macro porosity of the soil facilitating entry of rain water into soil which is crucial to rainfed fanning. Decrease in bulk density increases the rooting of sugarcane. It can also be used as a secondary tillage implement for harrowing of ploughed land. It is well adapted for field crops making it popular among farmers. Currently one unit is priced at US$ I00.Fertiliser ApplicatorThis implement is used to place and cover the fertilizer on eitherside of the cane row thus off barring and subsequent fertiliser application in sugarcane ratoons is carried in one operation. The prime mover of the implement is a 7.5 horsepower two-wheeled tractor commonly available with farmers (Fig. 3). Fig. 3. The fertiliser applicator developed by the SRI (1. Hitch Unit; 2. Braces; 3. Main Frame; Sprocket wheel & chain; 5. Front Axle; 6. Sub-frame; 7. Bracket; 8. Tine; 9. Fertilizer bin; 10. Rear Axle; 11. Adjustable opening; 12. Fertilizer chute; 13. Fertilizer tube; 14. Covering mechanism)In sugarcane farming fertiliser is applied three times in irrigated crops and twice in rainfed crops. For best results fertiliser should be applied to the root zone and then covered to reduce losses. Usually farmers use mammoty to open up a furrow on either side or one side of the cane row to apply fertiliser and cover up the same manually. which is an unsatisfactory practice. The other operation, referred to as off barring is used in ratoon cane to remove old roots by cutting them off before applying fertiliser.However, due to scarcity of labour and the high costs involved, these operations are neglected leading to poor crop and lodging of cane caused by shallow rooting. Apart from the use of mammoty, animal drawn mould board plough (country plough) is also used to make a shallow furrow by the side of cane row. However, this is not satisfactory as it neither breaks old roots in ratoons nor make a sufficiently deep fuffow to hold the fertiliser.The other option available for this purpose in Sri Lanka is the Australian design four-wheel tractor mounted disc ratooner available for off- barring. The implement consists of a tool bar and two disc units. Each disc unit consists of three concave discs mounted on a single axle. The horizontal and vertical adjustments of the disc units provide the required depth and width of cutting and inversion of soil. it is a satisfactory implement。It consists of a(a) frame,(b) fertiliser applicator mechancism,(c) two tines,(d) two soil-covering devices.The main frame is a truncated isosceles triangle made of mild steel angle iron. The truncated end of the triangle carries a hitch unit, which enables the implement to be attached to the two-wheel tractor. Two bolts are provided in the hitch for mounting the implement. Two parallel braces are provided between the hitch and the box beam for fixing the mixing mechanism and to ensure rigidity of the frame. The side beams of the frame are extended for mounting the fertiliser box and the mixing mechanism.Fertiliser bin has two adjustable openings and chutes, two fertiliser tubes and two mixers and their driving gear. The bin is the container for fertilizer. It has an inverted truncated prism shape. The lower part of the bin is segmented into two parts. Each part is provided with an opening and a sliding door to enable flow of fertiliser to be regulated. A conical fertiliser chute is fitted at the door to guide the flow of fertiliser. The two flexible tubes fitted to the chutes release the fertiliser to the two furrows opened by the tines. The mixing mechanism consists of two mixers, four sprocket wheels, two chains and two axles. The two mixers are provided at the bottom of the fertiliser bin to ensure continuous mixing of fertiliser. They are fitted to one axle and are driven by the main drive of the tractor through sprockets and chains. Mixers are driven by four sprocket wheels, one large and three smaller, two chains and two axles. The second and the third sprockets are fitted to an axle at the middle of the frame. The fourth sprocket is fitted to the axle with mixers. Mixing mechanism is driven by the main drive of the tractor through sprocket wheels and chains. The mixer drive continuously mixes the fertiliser for ensuring the continuous discharge at the required rate.The implement has two tines with replaceable shoes. It has a shank, replaceable shoe and a bracket with four bolts. The lower end of the shank is curved and in the curved end three bolt holes are provided for mounting the shoe. Working angle of the tines could be adjusted by changing the position of the fixing bolts of the tines. A conical end is welded just above the curvature of the shank to direct the fertiliser coming through fertiliser tubes to the point of application. Fertiliser coveting mechanism is also attached to the lower end of the shank.The covering mechanism is used to cover the fertiliser released into the furrow with loose soil thrown up by the tines. The implement can he adjusted for lateral spacing between the tines, angle of tines, and rate of fertiliser discharge. The latter is achieved by adjusting the sliding door to obtain the required discharge of fertiliser.The dimensions of the implement are: length- 750mm, width- 900mm, height- 700mm and weight- 45 kg. In sugarcane cultivation, the unproductive roots of the plant crop carried over to ratoons in the soil have to be shaved offto stimulate new roots. In earthing up or on baring soil is heaped around the two sides of the cane row, which prevents late tillering, reduces lodging and cover up the applied fertiliser reducing losses. The farmers due to scarcity of labour and high costs often neglect these.These generally carried out by small holders using mammoty. This requires 28- 30 labour units per hectare. Animal drawn mould board plough is also used but shallow furrow and the amount of soils inverted are not adequate for the purpose. The Australian design of four wheel tractor mounted disc ratooner having a tool bar and two discs gives a satisfactory performance。Fig. 4. Disc Ratooner1. Bracket; 2. Frame; 3. Disc Connector; 4. Disc; 5. Hitch unit; 6. Hinge Arrangement; 7. Bearing UnitThe disc ratooner invented by the SRI is shown in Fig 4 has a triangular steel frame and two disc units. A 7.5 horsepower two-wheeled tractor powers it. The frame is a truncated isosceles triangle made of rolled iron. The truncated end of the triangle carries a hitch point, which enables the implement to be attached to the two-wheel tractor. The three bolt holes are provided in the hitch, one for mounting purposes and the others for proper alignment. Each Disc unit has a mild steel shaft with a bracket for mounting to the frame, alloy steel serrated concave disc, a bearing unit with two bearings for mounting disc on the shaft and a hinge arrangement. The implement has horizontal spacing adjustment to adjust the spacing between discs; vertical height adjustment enabling the adjustment of the distance between the discs and the frame,disc angle can be adjusted by rotating the shaft carrying the disc unit and the tilt angle by adjusting the hinge arrangement. It has the following dimensions: 660mm length, 1050 mm width, 640 mm height and 45kg weight.Field tests show adjusting the horizontal and verticalangles of the discs and thus enabling it to cut and invert the required amount of soil in the desired way could control the amount of cut and inversion.It has a capacity of 0.07 ha per hour.Normally manual earthing up requires about 30 labour units per hectare and it is strenuous than most of the other cultural operations described earlier.Furrow OpenerFurrow opening after ploughing and harrowing of sugar cane fields is an essential operation for planting of sugarcane setts. No suitable furrow opener for two-wheel tractor for seedbed preparation is available.The implement designed by SRI has a frame, furrow bottom and two markers. The steel frame is triangular in shape and made of rolled angle iron. The front end of the frame carries a hitch unit by which the implement is attached to the tractor. Four bolt holes are provided in the hitch unit, two for mounting and the others for alignment purposes. The two adjustable markers with pointed arrows are provided for maintaining the spacing during the opening of furrows. The furrow bottom consists of a steel shank which is curved towards the front at the lower end, The implement has provision to adjust the angle of furrow bottom, which improves the performance and handling. REFERENCESDharmawardene, M.W.N (2003). A Collection of Essays on Sugar Sector of Sri Lanka. Dharmawardene, M.W.N. and Krishnamurthi, M (1992). An Outline Plan for the Development of the Sugar Industry of Sri Lanka. Witharama, W.R.G. (1999). Annual Agronomy Progress Report。斯里兰卡的农业机械化M.W.N.DHARMAWARDENE斯里南卡甘蔗研究所，斯里南卡摘要目前，农业生产机械化对于生存变得越来越重要， 影响国家所有种植作物的效率。即使对于生长在在干旱地区的甘蔗也没有例外。 实际上由于恶劣的气侯条件以及远离主要城市，因此在这些地区人口密度低，可利用的劳动力少。 因而劳工缺乏是在手工工作的甘蔗区域。 此外，由于温度高气候干燥、土壤坚硬、以及干风，劳动者容易疲倦。另外，工作的地方有大量的毒蛇，也使在这些地区工作的人们担心害怕。 因而，当工资一天天的上涨时，种植，除草以及收获装载这些工作往往做不好，从而导致农业损失。 通过对甘蔗耕种费用的分析表明， 运输费用（35%）以及准备费(21%)，种植(16%)，除草(l0%)，肥料(10%)和灌溉(8%)。显然在甘蔗生产过程中收获和装载的费用是最高的，而除草，施肥，发茬，接地，这些手工操作的劳动强度是很高的，小土地农场主往往忽略这些损失。 因此，应用小型农业机械来提高甘蔗生产率以及减轻劳动者的体力劳动变得很关键，目的是为了提高斯里南卡的甘蔗生产。某些小型的农田工具和器械已经应用在甘蔗生产上，例如由双轮拖拉机供给动力的SRI泰恩河耕地机、施肥器、旋耕器、犁沟器和新设计的甘蔗收获刀。 关键词： 甘蔗，农业机械化，斯里南卡介绍在斯里南卡农民将收获的甘蔗大量用于制糖， 这些小农场的范围从一公顷到五公顷不等。 除了使用常规农业机械进行的最初土地准备外，其余的操作例如从种植的到收获，都是使用手工方法，自己做或聘用劳工。对斯里南卡的这些小农场主生产甘蔗的成本分析来看，甘蔗的收获和装载 运输，种植，除草，施肥和灌溉占了大多数的开销，大多数劳动都是高强度的，既耗费时间又要忍受热带地区炎热的天气， 结果，这些繁重的工作人们大多不喜欢做。 因此，农民发现在一个特定的时期难以完成特定任务，从而影响甘蔗的产量的质量。经常注意到在这种热带地区的阳光炙烤下劳动者的体力在几小时内之内迅速下降，从而往往要停下休息而导致工作中断。因而，在甘蔗的手工耕种时，许多工作例如实时性除草，施肥，收获，很难雇佣到劳动力。在干燥的高海拔地区耕种找不到足够劳动力是很正常的。 也注意到许多农业地区的青年人口倾向于远离传统的农村而到遥远的都市漂泊。因而你会注意到小农场主将会大量依靠机械化从而提高生产力。在斯里兰卡在甘蔗的生产过程中由传统到机械化是由以下发展的： (a)传统手工工具 (b)被改进的手工工具 (c)利用牲畜 (d)以独轮车为代表的机械化(翻土机) (e)以四轮拖拉机为代表的机械化实际上，不同的工具用于甘蔗种植的不同区域。土壤的条件例如贫瘠的土壤经常限制上面前三个选择的有效率。虽然，使用上面的最后一个选择即用四轮拖拉机进行耕种可以用于改进生产力。即用四轮拖拉机来进行耕种实践，由农民支配机械运行，不过由于土地较少，以及对四轮拖拉机的不熟悉和较高的使用费用使它看起来不太适合这些斯里兰卡的已经习惯传统耕种的农民。 另一方面，大多数农民自己或是邻居都拥有一台熟悉的翻土机 (5到7 HP)，因为它们常用在低洼地区的水稻作业。 此外，对于那些翻土机而言，在那些区域进行必需的修理和其他服务是免费的。 然而，在斯里南卡，没有一种和这相