大卷装卷染机设计【含5张CAD图带开题报告-独家】.zip
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目 录1 英文文献翻译31.1英文文献原文题目31.2中文翻译182专业阅读书目292.1染整机械292.2纺织机械概论292.3纺织机械基础292.7 现代工程制图302.5纺织工艺设计312.6 机械设计课程设计312.7 机械零部件选用与设计322.8 材料力学332.9 机械原理332.10纺织机械常用手册341 英文文献翻译1.1英文文献原文题目Calculation of contact stress of mechanical parts.Abstract The hing-pairs mechanism of delivering power, e.g .friction wheel、protrusive wheel、gear、chain wheel、rolling bearing and rolling spiral ect.There are all the problem of contacting strength, contacting stress is also be involved naturally.Over-all discussions will proceed to the calculation of contacting stress here.Keywords contacting stress hertz-formulaTwo curved surface of the elastomer under the effect of pressure, the mutual contact, the contact stress can be generated transfer power of high vice institutions tend to appear in the job is alternating stress, contact stress by alternating the machine parts under certain conditions will appear the phenomenon of fatigue pitting, pitting spread to a certain degree, the parts cant use, that is to say the failure, the failure form of such as fatigue pitting damage, in ISO standard is based on the Hertz stress formula.In this paper, the Hertz stress formulae of several common surfaces and the calculation methods of contact stress for common mechanical parts are discussed in this paper, which is convenient for the design and strength checking of such parts.1 Stress concentration phenomena and conceptsThe damage caused by material under alternating stress is called fatigue failure.Usually, the deformation of the material is much less than the strength limit under its static load.In addition, the local increase of stress due to the change of section size is known as stress concentration.For components made of brittle materials, the stress concentration will remain until the maximum local stress reaches the limit.Therefore, stress concentration should be considered when designing brittle materials.For the components made of plastic materials, the stress concentration has little effect on the strength under static load.Therefore, when studying the static strength problem of the plastic material components, the effect of stress concentration is usually not considered.The stress on the cross section is distributed evenly in the region where the axial tension and compression are confined, and only in the area with a little distance and no drastic change in the cross section size.However, in actual engineering components, some parts often have incisions, grooves, oil holes, threads, etc., resulting in sudden changes in the sectional dimensions of these parts.Such as open hole and lath with incision, when its under axial tensile, within the local area near the round hole and incision, dramatic increase the value of stress, and where to leave the area is a bit far, tend to be more uniform stress reduced quickly.At this time, the stress on the cross section is no longer uniformly distributed, which has been proved by theory and experiment.Under static load, the sensitivity of various materials to stress concentration is different.When the maximum stress in the vicinity of the hole reaches the yield limit, the material first yields and the stress is no longer increased.Such as external forces continue to increase, increasing the stress is on the cross section has not yet to material yield, is a section on other points of stress increases to yield limit, the stress on the cross section gradually tends to the average, as shown in figure 2-32.Therefore, the effects of stress concentration can be neglected under static load with the parts made of plastic materials.In the case of uniform brittle material, the material does not yield, and when the maximum stress value of the hole reaches the strength limit of the material, it first breaks.Therefore, the stress concentration will greatly reduce the strength of the components, and the damage is serious.In this way, the effect of stress concentration on the bearing capacity of materials should be considered even under static load.For groups, however, heterogeneous brittle material, such as cast iron, its internal organization inhomogeneity and defects, and is often a major factor in the production of stress concentration, and the cross section shape change caused by stress concentration can be minor, it for component bearing capacity does not necessarily cause obvious problems.1.1 Some methods of avoiding stress concentration in reality.1.1.1 In packaging design, stress concentration is avoided and used.There is a significant increase of stress in the parts or components in the shape and size.If the transmission shaft shoulder Angle, key groove, oil hole and tight fit, the stress concentration after the stress.The peak stress of these sites decreased significantly from the concentration point to the adjacent area, which showed a high stress gradient.The early failure of parts often occurs in the area of stress concentration, so it is of great significance to understand and master the problem of stress concentration and to rationally design and reduce mechanical parts.In elastic mechanics, the phenomenon of stress in a solid local area increases significantly.It is often found in sharp corners, holes, gaps, grooves, and rigid constraints and their neighborhood.Stress concentration can cause brittle material fracture;To cause fatigue cracks in an object.In the stress concentration area, the maximum stress (peak stress) is related to the geometrical shape and loading method of the object.The stress value of local heighten decreases rapidly with the increase of the distance between the peak point.Because the peak stress often exceeds the yield limit and causes the redistribution of stress, the actual peak stress is often lower than the theoretical peak stress calculated by elastic mechanics.The parameter that reflects the increase of local stress is called the stress concentration factor k, which is the ratio between peak stress and stress concentration without considering stress concentration, which is greater than 1 and has no relation to the load size.In the case of one-way tension of the infinite plate, k = 3 on the edge of the circular hole;In the case of bending, the ratio between the radius of the different circular holes and the thickness of the plate is equal to 1.8 3.0;In the case of torsion, k = 1.6 4.0.In 1898 German g. kirsch first obtained the results of stress concentration near the circular hole.In 1910 Russias G.V. kolosov obtained a formula for the stress concentration near the elliptical hole.In the late 1920 s, the Soviet unions N.I. moose hurley mikheil saakashvili and others introduce the complex function elastic mechanics, using conformal mapping to a irregular piecewise smooth curve transformation to the unit circle, stress expression of complex function and its boundary conditions is derived, and then get a batch of exact solution of stress concentration.Various experimental methods have been developed rapidly, such as electrical measurement, photoelastic method, speckle interferometry, moire method and other experimental methods (see experimental stress analysis), which can measure the stress concentration of objects.In recent years, the rapid development of computer and finite element method and boundary element method has opened a new way to find the numerical solution of stress concentration.In order to avoid the damage caused by stress concentration, it can be used to eliminate the sharp Angle, improve the shape of the component, strengthen the hole edge and improve the surface finish of the material.In addition, the surface of the material can be sprayed, rolled and oxidized to improve the fatigue strength of the material surface.Using ANSYS to simulate the two-point symmetric loading of reinforced concrete beams, how can the concentrated load be arranged to avoid the premature failure of concrete?Add a pad at the loading point.It seems worth trying to apply the equivalent line load, but the line load distribution should not be too large!Role replacement, according to the equivalent load curve prestressed end axial force according to the actual pressure end plate anchorage size divide a surface, the surface pressure shaft, can solve the problem of excessive concentration.Design of the curtain wall ETFE membrane structure curtain wall of Beijing Olympic Games stadium (4) design of key nodes to avoid stress concentration;Abstract: to explore the weighted combination forecast method in the application of stress concentration problem, with holes pull board, for example, the data of the sample point, GM (1, 1) model is set up respectively, trend curve prediction model and the optimal weighted combination forecast model, and the error of each model and comparison. The results show that the combination forecast model fitting and forecast precision is higher than a single model. Therefore, using the optimal weighted combination forecast model to derive the maximum stress, stress, high is a kind of practical engineering testing data processing of the new method. The boundary element method in hatch corner corner stress concentration problem, the application of grey system model and its application in the stress concentration problem in the Angle of the engineering structure, gap, grooves, holes are stress concentration happens nearby, where near the hole stress increased local called hole edge stress concentration.In the water conservancy project, the stress local increase near the dam heel and the inside of the dam is a typical example of stress concentration.1.2.2 In practical engineering, the rounded corners avoid stress concentration.When making all kinds of pulling tools, the corners should be rounded at the corners, which is not for the sake of aesthetics. This is to avoid stress concentration.Stress concentration refers to the phenomenon that internal stress increases significantly in local area due to the abrupt change of geometrical shape and dimension.Stress concentration can cause fracture of components.The size of the rounded corners should be determined according to the size of the tool, too big influence tool effect, too small tool easily break damage.For the commonly used smaller drawing tools, the rounded radius is better than 2-3 mm, and the larger is about 5 mm.Tools for special shapes are determined based on actual conditions.But you have to have a rounded corner.2 The contact stress of any two surfaces.2.1 Coordinate systemFIG. 1 shows a part of a surface body, which is in contact with another surface body at E point, which is called the initial contact point.Take surface in E normal to the z axis, including z axis can have an unlimited number of cutting plane, each cutting surface with a plane intersection, the intersecting line is a plane curve, each plane curve has a radius of curvature in E.The curvature radius of the plane curve on the different cutting plane is generally not equal to the curvature radius of E.The radius of curvature has a maximum and minimum radius of curvature, called the principal curvature radius, R and R respectively, said the two radius of curvature in the direction of the, mathematics can be proved to be perpendicular.The plane of the plane curve AEB is yz plane, which gives us the position of x and y.Any contact surface can be used to determine the coordinate system.Due to the z axis is normal direction, so when two surface E contacts, z axis is overlap each other, between x1 and x2 , the angles between y1 and y2 in (figure 2).2.2 Contact stressTwo surface contact and compaction, pressure P along the z axis, near the initial contact point, the deformation of the material in the local by the contact point to form a small oval plane, elliptical semi-major axis on the x axis, a short half shaft on the y axis b (figure 3).The unit pressure size of each point on the elliptic contact surface is related to the deformation of the material. The deformation on the z-axis is large, and the maximum unit pressure will be generated along the z-axis.The other units of pressure P is P. Figure 1.Coordinates of the surface body Figure 2.Coordinate relation and contact ellipse.Figure 3. thecontactpressurel The equation forl specific pressurel total pressuredF In geometric terms is equal to the volume of the ellipsoid, soThe maximum unit pressure on the contact surface P 0 is called contact stressH （1）The size of a and b is related to the material and geometry of the contact surface.3 The contact stress of two spheres.When the two spheres of radius R 1 and R 2 are in contact with each other, under the action of pressure P, a circular contact area with a radius of a is equal to a=b(figure 4), which is obtained by the Hertz formula.In the formula :E 1 and E 2 are the elastic modulus of two spherical materials;The poisson of two sphere materials is one and two.The radius of the integrated curvature is R.If the materials of the two spheres are steel, E1 =E2=E, and1=2=0 .3, （2）If it is contact between two spheres (figure 5), the integrated curvature radius is.The contact stress can be calculated by substituting equation (2).If the sphere is in contact with the plane, R 2 is equal to infinity, then R =R1 is substituted into equation (2). Figure 4. Two balls in vitro contact Figure 5. Two balls on vitro contact4 The contact stress of two cylinders parallel to the axisparallel to the axis of two cylinders contact deformation before both along a straight line contact, pressing force P, the elastic contact point and contact wires into the rectangular surface width is 2 b (figure 6), unit according to the law of elliptic cylinder pressure distribution on the surface of the contact.The maximum pressure on the X-axis with the largest deformation is indicated by P 0. The pressure of the remaining points on the contact surface is distributed according to the semi-elliptic rule, as shown in fig.7. The volume of the semi-elliptical cylinder is equal to the total pressure P, so.Figure 6.Contact of two cylindersMaximum unit pressure (3)It is known by the Hertz formulaFigure7. The pressure distribution of two cylinders that are parallel to the axisPlug in type（3），soIf two cylinders are steel, E1 = E2 = E, u1 = u 2 = 0.3, P/L = q, 1 / R = 1/ R2 + 1 / R1, the contact stressIf the contact in the body of two beads (figure 8) is calculated by substituting 1/R=1/R1-1/R2 into equation (4), if the cylinder is in contact with the plane, R2= infinity, and R=R1 is substituted into equation (4). Figure8. Two cylinders in contact.5 Calculation of contact stress of mechanical parts.5.1 Friction wheel driveThe main form of the failure of the metal friction wheel drive is the fatigue point erosion of the rolling surface surface, and the contact stress on the contact surface of the rolling body is usually measured by the contact fatigue strength design.For the transmission of disc and friction wheel (figure 9), the pressure of the rolling body is substituted into the Hertz stress formula.Figure9. The disk is in contact with the friction wheel.Where :T is the torque on the friction wheel;F is the friction coefficient;B is the contact length;S is the friction margin, and the power transmission is between 1.25 and 1.5, which is not greater than 3 in the instrument transmission.5.2 Gear driveA pair of gears contact outside the node, which is equivalent to two cylinders with a radius of 1 and 2, which is also used in equation (4) to find the contact stress.By substituting formula (4), the contact stress formula of the gear surface can be obtained, and the design calculation formula of the contact strength of gear transmission is derivedFigure 10. The contact stress of a pair of gears at the node.5.3 Cam mechanismThe roller and CAM working face of CAM mechanism also have contact stress, which can be checked by formula (4).In the formula, q=P/ L, P is the normal pressure of the contact between the CAM and the push rod in the school nucleus, and the normal pressure of the normal roller push rod disc CAM mechanism is shown in figure 11.Where :Q is the load on the push rod;Alpha is the pressure Angle;F is the friction coefficient between the guide slot and the push rod;La is the length of the guide slot for the roller center on the push rod.5.4 Roller clutch (figure 12)When the clutch enters the joint state, the roller is wedged between the star wheel and the sleeve, and the sleeve will rotate with the star wheel. Figure 11. Force condition of CAM Figure 12. A schematic diagram of a roller-type directional clutch.The coordinates of the working face of the star wheel are the forces acting on the roller , the force on the clutch shaft, and the force on the roller, if the transmission moment is Mk,The contact of the roller and the star wheel is the contact of the cylinder and the plane, so the integrated curvature radius R=R1=d/2 unit length of the load q =Q/L, The contact stress formula between roller and star wheel can be obtained by substituting formula (4).Where: L is roller length;D is roller diameter.5.5 Contact stress between rolling body and raceway of rolling bearing.The contact between the roller bearing and the inner ring is equivalent to the outer contact of the two cylinders (figure 13) , The load q= P/L in the unit length is substituted into equation (4), and the contact stress of the roller with the maximum force and the contact of the inner ring can be obtained.In the formula :P is the force exerted by the most stressed roller;L is the roller working length.6 Epilog(1) based on the analysis of the high secondary contact stress between surfaces, the Hertz formula was further improved, and four contact stress calculation formulas were obtained.(2) some mechanical parts, such as the above discussion of the gears, the friction wheel, the rolling bearing is working in high contact pressure, after a lot of contact stress cycle, the local surface will be small pieces or small pieces of metal flake, the formation of pitting or pits, leads to increasing parts working noise and vibration.In this paper, the contact stress of these parts is given.Reference1 Wu zongze. Higher mechanical design. Beijing: tsinghua university press, 1991.2 us a. h. burr. Mechanical analysis and mechanical design. Beijing: mechanical industry press,1988.3 Xu zhen yu, qiu xuanhuai. Mechanical parts. Beijing: people education publishing house, 19814 Peter Johnson. Stress concentration factor in design1.2中文翻译机械零件的接触应力计算摘 要 传递动力的高副机构，如摩擦轮，凸轮齿轮，链轮齿轮，滚动轴承，滚动螺旋等，都有接触强度问题。自然也涉及到接触应力，在此对接触应力计算作较为全面的讨论。关键词 接触应力 赫兹应力公式 高副两曲面的弹性体在压力作用下,相互接触时,都会产生接触应力,传递动力的高副机构在工作中往往出现的是交变应力,受交变接触应力的机器零件在一定的条件下会出现疲劳点蚀的现象,点蚀扩散到一定程度,零件就不能再用了,也就是说失效了,这样失效的形式称之为疲劳点蚀破坏,在ISO 标准中是以赫兹应力公式为基础的。本文较为集中地讨论了几种常见曲面的赫兹应力公式及常用机械零件的接触应力计算方法,便于此类零件的设计及强度验算。1 应力集中现象及概念材料在交变应力作用下产生的破坏称为疲劳破坏。通常材料承受的交变应力远小于其静载下的强度极限时，破坏可能发生。另外材料会由于截面尺寸改变而引起应力的局部增大，这种现象称为应力集中。对于由脆性材料制成的构件，应力集中现象将一直保持到最大局部应力到达强度极限之前。因此，在设计脆性材料构件时，应考虑应力集中的影响。对于由塑性材料制成的构件，应力集中对其在静载荷作用下的强度则几乎无影响。所以，在研究塑性材料构件的静强度问题时，通常不考虑应力集中的影响。承受轴向拉伸、压缩的构件，只有在寓加力区域稍远且横截面尺寸又无剧烈变化的区域内，横截面上的应力才是均匀分布的。然而实际工程构件中，有些零件常存在切口、切槽、油孔、螺纹等，致使这些部位上的截面尺寸发生突然变化。如开有圆孔和带有切口的板条，当其受轴向拉伸时，在圆孔和切口附近的局部区域内，应力的数值剧烈增加，而在离开这一区域稍远的地方，应力迅速降低而趋于均匀。这时，横截面上的应力不再均匀分布，这已为理论和实验证实。在静荷载作用下，各种材料对应力集中的敏感程度是不同的。像低碳钢那样的塑性材料具有屈服阶段，当孔边附近的最大应力达到屈服极限时，该处材料首先屈服，应力暂时不再增大。如外力继续增加，增加的应力就有截面上尚未屈服的材料所承担，是截面上其他点的应力相继增大到屈服极限，该截面上的应力逐渐趋于平均，如图2-32所示。因此，用塑性材料制作的零件，在静载荷作用下可以不考虑应力集中的影响。而对于组织均匀的脆性材料，因材料不存在屈服，当孔边最大应力的值达到材料的强度极限时，该处首先断裂。因此用脆性材料制作的零件，应力集中将大大降低构件的强度，其危害是严重的。这样，即使在静载荷作用下一般也应该考虑应力集中对材料承载能力的影响。然而，对于组织不均匀的脆性材料，如铸铁，其内部组织的不均匀性和缺陷，往往是产生应力集中的主要因素，而截面形状改变引起的应力集中就可能成为次要的了，它对于构件的承载能力不一定会造成明显的问题。1.1 现实中避免应力集中的一些方法1.1.1包装结构设计中，应力集中避免与利用受力零件或构件在形状、尺寸急剧变化的局部出现应力显著增大的现象。如传动轴轴肩圆角、键槽、油孔和紧配合等部位，受力后均产生应力集中。这些部位的峰值应力从集中点到邻近区的分布有明显的下降，呈现很高的应力梯度。零件的早期失效常发生在应力集中的部位,因此了解和掌握应力集中问题，对于机械零件的合理设计和减少机械的早期失效有重要意义。弹性力学中的一类问题，应力在固体局部区域内显著增高的现象。多出现于尖角、孔洞、缺口、沟槽以及有刚性约束处及其邻域。应力集中会引起脆性材料断裂；使物体产生疲劳裂纹。在应力集中区域，应力的最大值（峰值应力）与物体的几何形状和加载方式等因素有关。局部增高的应力值随与峰值应力点的间距的增加而迅速衰减。由于峰值应力往往超过屈服极限而造成应力的重新分配，所以，实际的峰值应力常低于按弹性力学计算出的理论峰值应力。反映局部应力增高程度的参数称为应力集中系数k，它是峰值应力与不考虑应力集中时的应力的比值，恒大于1且与载荷大小无关。在无限大平板的单向拉伸情况下，其中圆孔边缘的k3；在弯曲情况下，对于不同的圆孔半径与板厚比值，k1.83.0；在扭转情况下，k1.64.0。1898年德国的 G.基尔施首先得出圆孔附近应力集中的结果 。1910年俄国的G.V.科洛索夫求出椭圆孔附近应力集中的公式。20世纪20年代末 ，苏联的N.I.穆斯赫利什维利等人把复变函数引入弹性力学，用保角变换把一个不规则分段光滑的曲线变换到单位圆上，导出复变函数的应力表达式及其边界条件，进而获得一批应力集中的精确解。各种实验手段的发展也很快，如电测法、光弹性法、散斑干涉法、云纹法等实验手段（见实验应力分析）均可测出物体的应力集中。近年来计算机和有限元法以及边界元法的迅速发展，为寻找应力集中的数值解开辟了新途径。为避免应力集中造成构件破坏，可采取消除尖角、改善构件外形、局部加强孔边以及提高材料表面光洁度等措施；另外还可对材料表面作喷丸、辊压、氧化等处理，以提高材料表面的疲劳强度。用ANSYS模拟钢筋混凝土梁两点对称加载，集中荷载如何布置才能避免应力集中造成混凝土过早破坏！ 在加载点加一个垫块。通过等效线荷载施加好像值得试试，不过线荷载分布长度不宜太大！曲线预应力筋作用按照等效荷载作用替代，端头轴力按照实际锚具承压端板大小划分一个面，在此面作用轴压力，可以解决集中力过大问题。 北京奥运会体育场游泳馆的幕墙 ETFE膜结构幕墙设计要点（4）关键节点的设计，以避免应力集中；摘要：探讨加权组合预测方法在应力集中问题中的应用,以带小孔的拉板为例,对采样点的数据分别建立GM(1,1)模型、趋势曲线预测模型和最优加权组合预测模型,并对各模型的误差和进行比较.结果表明,组合预测模型的拟合和预测精度比单个模型要高.因此,用最优加权组合预测模型来推求应力集中区的最大应力,是工程测试数据处理的一种比较实用的新方法.边界元法在舱口角隅应力集中问题中的应用灰色系统模型及其在应力集中问题中应用在工程结构的凹角、缺口、沟槽、孔洞附近均会发生应力集中，其中孔洞附近的应力局部增高称为孔边应力集中。在水利工程中，大坝的坝踵附近以及坝内廊道附近的应力局部增高是应力集中的典型实例。1.1.2 实际工程中圆滑的角避免应力集中在制作各种拉力工具时，拉脚的拐弯处应设圆角，这并不是为了美观，这是为了避免应力集中。应力集中指由于受力构件由于几何形状、外形尺寸发生突变而引起的局部范围内内应力显著增大的现象。应力集中会造成构件的断裂。圆角的大小应根据工具的外形尺寸决定，太大影响工具的效应，太小工具容易断裂损坏。对于常用的较小拉制工具，圆角半径在2-3毫米为佳，较大在5毫米左右。对于特殊形状的工具根据实际情况确定。但或大或小必须留圆角。2 任意两曲面体的接触应力2.1 坐标系图 1 所示为一曲面体的一部分 ,它在 E 点与另外一曲面体相接触 , E 点称为初始接触点 。取曲面在 E 点的法线为z 轴 ,包括 z 轴可以有无限多个剖切平面,每个剖切平面与曲面相交 ,其交线为一条平面曲线 ,每条平面曲线在E 点有一个曲率半径 。不同的剖切平面上的平面曲线在 E 点的曲率半径一般是不相等的。这些曲率半径中 ,有一个最大和最小的曲率半径, 称之为主曲率半径 ,分别用 R和 R表示 ,这两个曲率半径所在的方向 ,数学上可以证明是相互垂直的 。平面曲线 AEB 所在的平面为yz 平面,由此得出坐标轴 x 和y 的位置 。任何相接触的曲面都可以用这种方法来确定坐标系 。由于 z 轴是法线方向 ,所以两曲面在 E 点接触时, z 轴是相互重合的, 而 x1 和 x2之间 、y 1和 y2之间的夹角用表示(图 2所示)。2.2 接触应力两曲面接触并压紧,压力 P 沿 z 轴作用, 在初始接触点的附近 ,材料发生局部的变形 ,靠接触点形成一个小的椭圆形平面 , 椭圆的长半轴 a 在 x 轴上,短半轴 b 在 y 轴上(图 3)。椭圆形接触面上各点的单位压力大小与材料的变形量有关 , z 轴上的变形量大 ,沿 z 轴将产生最大单位压力P0 。其余各点的单位压力 P 是按椭圆球规律分布的。其方程为：单位压力：总压力：dF 从几何意义上讲等于半椭球的体积 ,故接触面上的最大单位压力 P 0 称为接触应力H (1)a 、b 的大小与二接触面的材料和几何形状有关。3 两球体的接触应力 半径为 R 1 、R 2 的两球体相互接触时,在压力 P的作用下, 形成一个半径为 a 的圆形接触面积即a=b(图4),由赫兹公式得式中：E 1 、E 2 为两球体材料的弹性模量;1 、2 为两球体材料的泊松。取综合曲率半径为 R ,则若两球体的材料均为钢时 , E1 =E 2 =E , 1 =2 =0 .3,则 (2)如果是两球体内接触(图 5),综合曲率半径为代入式(2)计算即可求出接触应力H 。如果是球体与平面接触 ,即 R 2 =,则 R =R1代入式(2)计算即可。4 轴线平行的两圆柱体相接触时的接触应力轴线平行的两圆柱体接触时,变形前二者沿一条直线接触,压受力 P 后, 接触处发生了弹性变形 ,接触线变成宽度为 2b 的矩形面(图 6), 接触面上的单位压力按椭圆柱规律分布。变形最大的 x 轴上压力最大, 以 P 0 表示, 接触面上其余各点的压力按半椭圆规律分布 ,如图7， 半椭圆柱的体积等于总压力P,故最大单位压力 （3）由赫兹公式知代入式（3），得若两圆柱体均为钢时，E1=E2=E, 1=2=0.3,取P/L=q,1/R=1/R1+1/R2,则接触应力为若为两圆珠体内接触（图8），则以1/R=1/R1-1/R2代入式（4）计算，若是圆柱体与平面接触，则R2=, ,R=R1代入式（4）计算5 机械零件的接触应力计算5.1 摩擦轮传动金属摩擦轮传动失效的主要形式是滚动体表面的疲劳点蚀, 常按接触疲劳强度设计, 来验算滚动体接触表面上的接触应力 。对于圆盘与摩擦轮的传动(图 9),将滚动体的压紧力 代入赫兹应力公式 ,可得式中:T 为摩擦轮轴上转矩 ;f 为摩擦系数;b为接触长度;S 为摩擦力裕度, 在动力传动中取1.25 1.5,在仪器传动中取不大于 3 。5.2 齿轮传动一对齿轮在节点外接触, 相当于半径为 1、2的两个圆柱体相接触(图 10), 因此也用式(4)来求接触应力代入式（4），便可得出齿轮表面的接触应力公式，进而导出齿轮传动接触强度的设计计算公式。5.3 凸轮机构凸轮机械中滚子与凸轮工作面也存在着接触应力,也可以用式(4)进行校核式中:q=P/ L , P 为凸轮与推杆间在所校核的接触处的法向压力, 常见的直动滚子推杆盘形凸轮机构法向压力如图 11 所示。式中:Q 为推杆上的载荷；为压力角；f 为导槽与推杆间摩擦系数；La为推杆上滚子中心伸出导槽的长度5.4 滚柱式离合器(图 12)当离合器进入接合状态时 ,滚柱被楔紧在星轮和套筒间 ,靠套筒随星轮一同回转 。星轮工作面的坐标为 作用在滚柱的力对离合器轴心的力臂为 若传递的传矩为Mk时,作用在滚柱上的力为 滚柱和星轮的接触是圆柱体和平面相接触, 所以综合曲率半径R=R1=d/2 单位长度的载荷 q =Q/L ,代入式(4)即可得出滚柱和星轮间的接触应力公式式中：L 为滚柱长度；d 为滚柱直径。5.5 滚动轴承的滚动体与滚道间的接触应力滚子轴承的滚子与内环的接触相当于两圆柱体外接触(图 13),综合曲率半径 ,单位长度上的载荷q= P/L 代入式(4),便可得出受力最大的滚子与内环接触处的接触应力式中 :P 为受力最大的滚子所承受的力;L 为滚子工作长度 。6 结语(1)通过对曲面间高副接触应力的分析 ,对赫兹公式进一步作了改进, 得到了 4 个接触应力计算公式。(2)有些机械零件, 如上述讨论的齿轮 ,摩擦轮、滚动轴承等都是工作在高的接触压力作用下, 经过多次接触应力循环下 ,局部表面将发生小片或小块金属剥落, 形成麻点或凹坑, 使零件工作时噪音增大, 振动加剧 。本文对以上这类零件的接触应力都给出了具体的计算公式参考文献1 吴宗泽.高等机械设计.北京:清华大学出版社, 1991.2 美 AH伯尔.机械分析与机械设计.机械工业出版社,1988.3 许镇宇, 邱宣怀.机械零件.北京:人民教育出版社, 1981.4 R.E.彼德逊. 设计中的应力集中系数.2专业阅读书目2.1 染整机械 内容摘要：纺织机械系列教材：染整机械是“纺织机械系列教材”之一。以工艺为纽带，重点介绍染整加工过程中的设备组成、工作原理和结构特点等。还对近年来的新型染整设备和未来发展趋势作了具体的阐述。 书中着重介绍了染整机的机械特点，染整机的现况及基本技术要求、染整机的发展趋势。同时介绍了几种染整机：卷染机、轧卷式染色机、连续轧染联合机、小批量连续轧染机、高温高压连续轧染机、印花联合机、织物整理机、针织物染色机械、毛织物整理机械及丝织物整理机械。其中书中详细的介绍了各种纺织类的机械，对各种机械的设计原理，工作原理，维护及保养的原理都做了详细的介绍。（盛慧英.染整机械M.北京：中国纺织出版社，2000）2.2纺织机械概论 内容摘要：本书介绍了纺织机械的分类，分析了纺纱机械、织造机械、针织机械、非织造机械、染整机械、化纤机械的基本工艺原理、核心技术、关键机构，还简要介绍了国内外纺织机械制造业的现状、光机电一体化技术在各类纺织机械上的应用情况以及现代纺织机械设计的发展趋势等。纺织机械涵盖了从纤维制备到服装成型过程中的所以加工设备，具体包括化纤机械、纺织机械、织造机械、针织机械、染整机械、非织造机械、服装机械及纺织器材八个相对独立的子行业。化纤机械：向生产技术的高效率、短流程、连续化、自动化方向发展。纺织机械：广泛应用电子技术、在线检测监控、使设备简单、操作方便、工艺适应性强、质量可靠、实现高速高产、优质、高效及节能等功能。（陈革.纺织机械概论M. 北京：中国纺织出版社，2011）2.3纺织机械基础 内容摘要：本书主要介绍了纺织机械通用零件结构的知识，纺织机械的基本原理和结构。主要包括：纺织机械的常用材料、机构，摩擦润滑知识及整经、倍捻、浆纱等前道准备机械和织机的开口、引纬、打纬、卷取、送经等机构的基础内容。第一节我国古代纺织业和纺织设备的发展概况第二节纺织机械分类第二章纺织机械常见机构及传动原理第一节有关机构的基本概念、构件、自由度和约束、运动链第二节机构运动简图及自由度计算、机构运动简图画法、平面机构的自由度计算第三节纺织机械常见机构、平面连杆机构、凸轮机构、齿轮机构四、间歇运动机构第三章纺织机械常用零件第一节螺纹及连接、螺纹及基本参数、螺纹连接的类型和螺纹紧固件、螺纹连接的预紧和防松第二节键连接、松连接、紧连接第三节销连接第四节轴连接、轴及轴承、联轴器及离合器、弹簧、弹簧变形能第四章传动机构第一节带传动一、带的分类、带传动的张紧及维护、带传动的维护、同步齿形带传动。（孟长明.纺织机械基础M. 北京：中国纺织出版社，2011）2.7 现代工程制图内容摘要：在工程设计中，为了正确地表达仪器、设备的形状、结构和材料等内容，设计者通常把物本按一定的投影方法并遵守有关的规定绘制出图纸，用以表达设计思想，这种图称为工程图。工程图是加工、制造、检验仪器和设备的依据。在使用仪器和设备时，也需要通过工程图了解义器和设备的结构和性能。工程图是工程界的一种重要技术文件，也是工程界进行技术交流的工具，因此工程图样被称为工程界的语言。 在现代工业生产中，工程图样作为表达构思、设计和传递制造工程与产品信息的主要媒介，在国民经济各领域的技术工作和管理工作中有着广泛的应用。在科学研究中，图形能直观表达实验数据、反映科学规律，对于人们把握事物的内在联系，掌握问题的变化趋势，具有重要意义。图形的形象性、直观性和简洁性，是人们认识规律、探索未知的重要工具。因此。工程图学对于新世纪大学生是一种素质，是一种工具，是培养创新思维的基础知识。 工程图学课程是高等工科学校各专业的一门技术基础课。其理论严谨，与工程联系紧密，实践性强，是后续专业课程教育的基础。该课程是一门研究在平面上图示空间几何元素和物体、图解空间几何问题的原理与方法，研究计算机绘图的理论、知识和技能，以及根据工程技术的规定和知识来绘制、阅读工程图样的学科。本课程将以正投影的基本原理为理论基础，讲述工程图样在构思、设计、图解空间几何问题的过程中，以及分析、研究自然界与工
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