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,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,平键构造示意图：,b,d-t,t,d+t,1,h,d,L,A,A,A,A,矩形花键构造例如：,The Tolerance of Key and Spindle,键和花键的公差,Outline,the type and function of key.,键的类型和作用,(2)Key associated parts include key,shaft and wheelrim.,键的联接件包括键、轴和轮毂槽,(3)The fit and tolerance of key.,键的配合与公差,The tolerance band of key is,h8.,键的公差带代号是,h8.,b.The type of fit,配合类型,common join,一般联接,tighter join,较紧联接,slacker join,较松联接,7.1 Key and Key Associated Parts,键和键联接件,fitted surface R,a,m,配合面,R,a,1.6,到,m,unfitted surface R,a,from 6.3 to 10,m,非配合面,R,a,6.3,到,10,m,c.Surface finish 外表粗糙度,(4)figure and positional tolerance choose,形位公差的选择,7.2 Spindle Parts,花键联接,The function of spindle,花键的作用：,1.,滑动联接；,2.,固定联接,(2)The spindle parts,花键副,(3)Dimension parameter,尺寸参数,(4)The tolerance of standard is the principle of standard hole.,花键副为基孔制配合,(5)The type of fit:,配合类型,a.According to function,根据功能,slide join,b.According to assemble tight slide join,fixed join,滑动联接,根据联接,紧滑动联接,固定联接,(6)The mark of spindle(example):,花键标记,a.spindle standard,花键标准尺寸,:823266.,b.inside spindle,内花键,:823H726H106H11.,c.outside spindle,外花键,:823f726a116d10.,d.spindle parts,花键副,平键公差带图：,+0,-,b,h9,H9,D10,h9,N9,JS9,h9,P9,P9,键宽公差带,轴槽公差带,轮毂公差带,较松键联结,一般键联结,较紧键联结,例题：某减速器传递一般扭矩，其中某一齿轮与轴之间通过平键联结来传递扭矩。键宽b=8mm，试确定键宽b的配合代号，查出其极限偏向值，并作出公差带图。,解：1键宽b的配合代号为h9，轴槽宽为N9，毂槽宽为Js9。,2查表得出极限偏向值为：,键宽,轴槽宽,毂槽宽,3公差带如答案图：,例题：某机床变速箱中，有一个6级精度齿轮的花键孔与花键轴联结，花键规格：626306，花键孔长30mm，花键轴长75mm，齿轮花键孔经常需要相对花键轴作轴向挪动，要求定心精度较高。试确定,1齿轮花键孔和花键轴的公差带代号，计算小径、大径、键槽宽的极限尺寸；,2分别写出在装配图上和零件图上的标记；,3绘制公差带图，并将各参数的根本尺寸和极限偏向标注在图上。,解：根据条件可知花键联接的配合应选用精细传动用的紧滑动配合，且应将内花键的小径公差带代号选为H6。,查表得花键孔和花键轴的公差代号为：,花键孔 626H630H106H9,花键轴 626g630a116f7,Bolt fastening,螺栓连接,Stud fastening,双头螺柱连接,Cap screws and set screws,螺钉及紧定螺钉的连接,The Tolerance of Thread,螺纹公差,Key words:,Bolt,螺栓,stud,螺柱,screw,螺钉,Washer,垫圈,Nut,螺母,standard elements,标准件,fastener,连接件,thread depth,螺孔深,depth of drilled hole,钻孔深,clearance hole,光孔,set screws,紧定螺钉,Key words:,8.1 Outline,(1)The type of thread,螺纹类型,(2)The parts of thread associated,螺纹组件,8.2 The Tolerance and Fit of Common Thread,普通螺纹的公差与配合,1.,The tolerance grade,螺纹的公差等级,inside thread,内螺纹,Outside,thread,外螺纹,Common tolerance grade of thread is IT6.,螺纹的常用公差等级为,IT6,2.The basic deviation of thread螺纹的根本偏向,The deviation sign of D2 and D1 choose G,H,the basic deviation is EI.,内螺纹中径D2、小径D1径根本偏向代号为G,H,根本偏向为,下偏向EI.,(2)The deviation sign of d2 and d1 choose e,f,g,h,the basic deviation is es.,外螺纹中径d2、大径d根本偏向代号为e、f、g、h,根本偏,差为上偏向es.,螺纹中径和顶径的根本偏向：,3.,Rotational length and fit grade,(1)Rotational length,旋合长度,middle rotational length N,中旋合长度,long rotational length L,长旋合,short rotational length S,短旋合,Note:,common thread choose N.,注意：螺纹常用旋合长度为中旋合。,(2)Fit grade,配合等级,precise grade precise thread,精细级用于精细螺纹,common grade common thread,中等级用于一般机械、仪表、构件的螺纹,rough grad low demand,machine difficultly,粗糙级用于精度不高制造困难的螺纹,4.,The tolerance band and using,公差带应用,5.,The mark of thread,(,example,),螺纹标记,(1)Outside spindle:M10,-,5g6g,-,L.,(2)Inside spindle:M101 L,-,6H.,M 20 2 LH-5g 6g-s,Major diameter d,20,Pitch=2(fine metric thread),Thread engagement group is short,Crest diameter tolerance symbol,Left hand,Pitch diameter tolerance symbol,Ex1,：,Metric thread,Tr407(14/2),7H,L,Major diameter d,40,Pitch=7 Lead=14 Multiple thread,Thread engagement group is long,Pitch and Crest diameter tolerance symbol,Right hand,Ex2,：,Trapezoidal thread,10 Dimension Stacking,尺寸链,C,=,A,+,B,increasing type C,decreasing type A,在尺寸链线图中，常用带单箭头的线段表示各环，箭头仅表示查找尺寸链组成环的方向。与封闭环箭头方向一样的环为减环，与封闭环箭头方向相反的环为增环。,A,3,A,2,A,0,A,1,B,0,B,2,B,4,B,5,B,1,B,3,与封闭环箭头方向一样的环为减环，与封闭环箭头方向相反的环为增环。,increasing type A1A3,decreasing type A2,increasing type B2B4B5,decreasing type B1B3,在装配尺寸链中，封闭环就是产品上有装配精度要求的尺寸。如同一部件中各零件之间互相位置要求的尺寸或保证互相配合零件配合性能要求的间隙或过盈量。,零件尺寸链的封闭环应为公差等级要求最低的环，一般在零件图上不进展标注，以免引起加工中的混乱。,工艺尺寸链的封闭环是在加工中最后自然形成的环，一般为被加工零件要求到达的设计尺寸或工艺过程中需要的余量尺寸。加工顺序不同，封闭环也不同。所以工艺尺寸链的封闭环必须在加工顺序确定之后才能判断。一个尺寸链中只有一个封闭环。,10.3 Tolerance of Dimension Stacking,(1)General Rule:Tol.of,X,=,Tol,.,of constituent dimensions:,So Tol.,X,=,Tol.,=,0.6.,Fig.10.4 Tolerance of dimension stacking,
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