白川夹具说明书

沈阳理工大学应用技术学院课程设计说明书I机械制造装备设计课程设计说明书题目圆柱形导柱轴承上盖支承座钻水平小孔系机械工程系专业机械设计制造及其自动化班级101211姓名白川川学号20指导教师王晓方完成日期2012年2月28日沈阳理工大学应用技术学院沈阳理工大学应用技术学院课程设计说明书II目录前言·······································································································11.设计过程··································································································21.1夹具的分析·························································································21.2零件的分析·························································································21.2课题（提供的技术资料）······································································41.2.1生产纲领·························································································41.2.2技术资料·························································································41.3毛坯种类····························································································42.定位基准及方案的确定···············································································42.11定位基准的选择原则···········································································42.12粗基准的选择原则··············································································42.13精基准的选择原则··············································································53.定位误差的分析························································································63.1定位误差····························································································63.2产生定位误差的原因·············································································73.3定位误差的计算···················································································74.夹紧装置的设计························································································85.夹紧力计算·······························································································96.导向装置的选择······················································································107.机床夹具的总体设计·················································································117.1确定夹具体························································································117.2确定联接体························································································118.结论······································································································129.设计体会及收获······················································································13参考文献··································································································14沈阳理工大学应用技术学院课程设计说明书1前言铣床指主要用铣刀在工件上加工各种表面的机床。通常以铣刀旋转运动为主运动，工件和铣刀的配合移动为进给运动。它可以加工平面、垂直面、斜面、各种沟槽或成型面，如果配一些附件(如分度头)也可以加工螺旋槽凸轮、成型面等。夹具是在机械制造过程中，用来固定加工对象，使之固定在正确的位置，以接受加工或检测并保证加工要求的机床附加装置，简称夹具。在实际生产中夹具的作用是将工件定位，以使加工工件获得相对于机床和刀具的正确位置，并把工件可靠地夹紧。夹具是在机床机械制造过程中，用来固定加工产品，使之固定在正确的位置，以接受加工或检测的机床附加装置，简称为夹具。实际生产中夹具的作用是将工件定位，以使加工工件获得相对于机床和刀具的正确位置，并把工件可靠地夹紧。在机床上加工工业零件时，必须用夹具装好固定所要加工工件。将工件装好，就是在机床上确定工件相对于刀具的正确位置，这一过程称为定位。将工件夹紧，就是对工件施加作用力，使之在已规定好的位置上可靠地固定，这一过程称为夹紧。从定位到夹紧的全过程，称为装夹。铣床夹具的主要功能就是完成工件的装夹固定工作。工件装夹情况的好坏，将直接影响工件的加工精度。通过生产实习、课程设计、实验等实践环节，熟悉制订工艺规程的原则、步骤和方法，对一般机械零件，具备制定机械加工工艺规程和装配工艺的能力。初步具备综合分析机械机械制造过程中提高产品质量和生产率，降低生产成本等方面问题的能力。对制造技术的新发展有一定的了解。沈阳理工大学应用技术学院课程设计说明书21.设计过程1.1夹具的分析机床夹具应满足的基本要求包括下面几方面：1)保证加工精度这是必须做到的最基本要求。其关键是正确的定位、夹紧和导向方案，夹具制造的技术要求，定位误差的分析和验算。2)夹具的总体方案应与年生产纲领相适应在大批量生产时，尽量采用快速、高效的定位、夹紧机构和动力装置，提高自动化程度，符合生产节拍要求。在中、小批量生产时，夹具应有一定的可调性，以适应多品种工件的加工。3)安全、方便、减轻劳动强度机床夹具要有工作安全性考虑，必要时加保护装置。要符合工人的操作位置和习惯，要有合适的工件装卸位置和空间，使工人操作方便。大批量生产和工件笨重时，更需要减轻工人劳动强度。4)排屑顺畅机床夹具中积集切屑会影响到工件的定位精度，切屑的热量使工件和夹具产生热变形，影响加工精度。清理切屑将增加辅助时间，降低生产率。因此夹具设计中要给予排屑问题充分的重视。5)机床夹具应有良好的强度、刚度和结构工艺性机床夹具设计时，要方便制造、检测、调整和装配，有利于提高夹具的制造精度。该课程设计主要是针对梯形块铣燕尾槽加工夹具的设计。铣床夹具主要用于加工零件上的平面、凹槽、花键及各种成型面，是最常用的夹具之一。铣削加工时切削用量较大，且为断续切削，故切削力较大，冲击和震动比较严重，因此设计铣床夹具时，应注意工件的装夹刚性和夹具在工作台上的安装平稳性。按铣削时的进给方式，可将铣床夹具分为直线进给式、圆周进给式和靠模进给式三种。直线进给式夹具安装在工作台上，加工中随工作台按直线进给方式运动。1.2零件的分析本次课设是要为此图中燕尾槽设计一个铣槽的夹具，最终实现将工件定位，更加精确和方便的完成铣削工作，并保证能夹紧工件，夹紧力要适中，不要使工件变形，又能保证工件所要求的加工精度。沈阳理工大学应用技术学院课程设计说明书3图1.1零件图标出了工件的尺寸、形状和位置、表面粗糙度等总体要求，它决定了工件在机床夹具中的放置方法，是设计机床夹具总体结构的依据,本工件放置方法应如图1所示。工序图给出了零件本工序的工序基准、已加工表面、待加工表面，以及本工序的定位、夹紧原理方案。工件的工序基准、已加工表面决定了机床夹具的方位方案，如选用平面定位、孔定位以及外圆面定位等；定位方案的选择依据六点定位原理和采用的机床加工方法，定位方案不一定要定六个自由度，但要完全定位。工件的待加工表面是选择机床、刀具的依据。确定夹紧机构要依据零件的外型尺寸，选择合适的定位点，确保夹紧力安全、可靠同时夹紧机构不能与刀具的运动轨迹相冲突。1.2课题1.2.1生产纲领工件的年生产量是确定机床夹具总体方案的重要依据之一。如工件的年生产量很大，可采用多工件加工、机动夹紧或自动化程度较高的设计方案，采用此方案时，机床夹具的结构较复杂，制造成本较高；如工件的年生产量不大，可采用单件加工，手动夹沈阳理工大学应用技术学院课程设计说明书4紧的设计方案，以减小机床夹具的结构复杂程度及夹具的制作成本。生产批量为20000件。1.2.2技术资料1、有要求尺寸精度：2、加工表面粗糙度：3、热处理的表面：1.3毛坯种类零件材料为HT200。灰铸铁生产工艺简单，铸造性能优良。考虑零件在机床运行过程中所受冲击不大，零件结果又比较简单，故选择铸件毛坯。2.定位基准及定位方案的确定2.1定位基准的选择原则2.1.1粗基准的选择原则1、保证零件的加工表面相对于不加工表面，有一定的位置精度原则2、合理分配加工余量原则3、易于装卡原则4、粗基准不得重复使用原则5、选择余量最小的表面做粗基准2.1.2精基准的选择原则1、基准重合原则2、基准统一原则3、互为基准原则4、自为基准原则5、定位准确，卡紧可靠，操作方便2.1.3定位元件的选择定位元件及定位装置是用于确定工件正确位置的元件或装置，常见的定位元件有支承钉、支承板、V形块、定位套、锥度心轴等等。在夹具设计中，定位方案不合理，沈阳理工大学应用技术学院课程设计说明书5工件的加工精度就无法保证。工作定位方案的确定是夹具设计中首先要解决的问题。根据工序图给出的定位元件方案，按有关标准正确选择定位元件或定位的组合。在机床夹具的使用过程中，工件的批量越大，定位元件的磨损越快，选用标准定位元件增加了夹具零件的互换性，方便机床夹具的维修