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WANG Jian LUO Shanming CHEN Lifeng CHEN Lei HU Huarong 《机械工程学报(英文版)》2008,21(3):94-98
Based on the mathematical model of a novel cosine gear drive, a few characteristics, such as the contact ratio, the sliding coefficient, and the contact and bending stresses, of this drive are analyzed. A comparison study of these characteristics with the involute gear drive is also carried out. The influences of design parameters including the number of teeth and the pressure angle on the contact and bending stresses are studied. The following conclusions are achieved: the contact ratio of the cosine gear drive is about 1.2 to 1.3, which is reduced by about 20% in comparison with that of the involute gear drive. The sliding coefficient of the cosine gear drive is smaller than that of the involute gear drive. The contact and bending stresses of the cosine gear drive are lower than those of the involute gear drive. The contact and bending stresses decrease with the growth of the number of teeth and the pressure angle. 相似文献
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直齿面齿轮加载啮合有限元仿真分析 总被引:20,自引:0,他引:20
研究正交面齿轮在加载条件下面齿轮啮合的传动性能参数、齿面接触应力和轮齿弯曲应力变化规律的有限元分析计算关键技术,以赫兹接触应力解析公式计算结果为对比,提出接触应力和弯曲应力计算的有限元网格密度确定方法。根据面齿轮重合度,分析面齿轮加载啮合仿真的五齿模型和七齿模型适用场合,给出面齿轮在啮合过程中的齿面接触应力和齿根弯曲应力最大值位置,计算面齿轮多齿模型接触应力及弯曲应力极值,准确得到面齿轮传动的重合度、传动误差、载荷分布系数等传动性能参数,以及载荷对这些传动性能参数的影响规律。研究结果表明,赫兹接触应力解析公式计算的结果合理地确定了有限元模型的网格密度,有限元仿真得到的应力值可靠,传动性能参数的分析结论正确。 相似文献
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In simulation of the three-dimensional contact problem for a longitudinally modified (barrel-shaped) gear tooth in cylindrical
involute transmissions, account is taken of the skew of the gear axes due to manufacturing and assembly errors and also deformation
of the drive components under load. The formulas, tables, and graphs presented are convenient for engineering calculation
of the flexural stress in the base of the teeth. On that basis, strength estimates may employ the limiting stresses recommended
by the relevant standard for linear contact of unmodified teeth. 相似文献
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A. A. Zhukov A. P. Navoev V. A. Zhukov S. V. Korytov 《Russian Engineering Research》2009,29(2):122-125
It has been analyzed the stressed state of diesel drive gear of YaM3 model. It is shown that if the fuel injection pressure is increased, the contact and bending stresses in the gears increase. It has been obtained the relationships between the gear stresses and the fuel pump torque, which is determined by injection pressure. 相似文献
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轮轨间的液态介质和表面微观粗糙度对接触表面疲劳损伤的影响 总被引:6,自引:0,他引:6
研究了具有表面微观粗糙度和有液态介质存在于接触表面的轮轨弹塑性接触力学问题,获得了轮轨表面接触应力分布等结果。结果表明,对于有表面微观粗糙度的轮轨,在接触区会出现很大的峰值接触应力,并造成轮轨表面出现塑性。在当载荷卸掉后,钢轨表面还存在严重的残余应力。在列车的多次运行过程后,这样的塑性变形会积累,以至疲劳破坏。给出了接触表面有液态介质和无液态介质的接触应力和残余应力结果。同时还分析了在有液态介质和无液态介质情况下,不同位置的表面微裂纹的裂纹尖端应力,结果表明在有液态介质存在下微观裂纹更易扩展,易导致轮轨表面剥离和断裂。 相似文献
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For a V-belt drive system, the effect of angular speed on the three-dimensional frictional contact behaviors on the contact surfaces between the V-belt and pulley flange is studied in this work. To deal with the frictional contact phenomena for the V-belt drive system, an effective three-dimensional finite element procedure is developed herein. By this procedure, the deformation of the V-belt and the normal/tangential contact forces occurring on the contact surfaces can be estimated accurately. The friction angles of contact points along the edge of the V-belt cross section are also presented for various dynamic friction coefficients. From the computed results, it is found that smaller friction angles are obtained as dynamic friction coefficients get larger. The results achieved are very helpful for the estimation of operation efficiency of the V-belt drive system. 相似文献
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Residual stresses are introduced and modified during manufacturing as well as by normal use under rolling contact loading. Operations such as heat treatments, shot peening, grinding, etc., are known to alter the magnitude and distribution of residual stresses. Our work revolves around the changes in magnitude and distribution of residual stresses, as they relate to deformation and the strain induced transformation of retained austenite. The residual stresses and retained austenite measurements were carried out using X-ray diffraction techniques. The rolling contact fatigue lives of different variants of SAE 52100 bearing steel were evaluated in a 5-ball-rod rolling contact fatigue machine under testing conditions leading to surface nucleated failure, i.e. non-ideal rolling contact. The tests were accelerated by applying well controlled micro-indentations on the wear track. The contribution of the residual stresses and amount of retained austenite to the rolling contact fatigue life were analyzed. 相似文献
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A numerical simulation technique for calculating the complete subsurface stress field for three-dimensionally rough bodies in sliding contact is described. The stresses are calculated using real digitized three-dimensional surface profiles. The effects of the surface roughness and the sliding friction are presented. Using an existing contact simulation code, the digitized surfaces are mathematically pressed together and the real areas of contact and the asperity pressures are calculated. The surfaces are assumed to remain elastic throughout the contact simulation process. The shear forces at the asperity contact interfaces are assumed to be proportional to their calculated normal pressures. The subsurface stresses are then determined with these known normal and tangential forces at the surface. 相似文献
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A.L. Kalamkarov 《International Journal of Mechanical Sciences》1997,39(7):873-883
A new inverse problem approach is introduced to analyse the stresses in the overlap elastic joint structures consisting of two adherents and an adhesive interlayer. Displacements in the elements of a joint are expressed in terms of some initially unknown contact stresses by solving the boundary-value problem for each element considered separately. The contact stresses are calculated from the matching continuity conditions for the displacements. Contact tearing and shear stresses, three-dimensional stress distribution in the bulk of adhesive interlayer, and the maximum stress values are calculated for different ratios of thicknesses and material properties of the adherents and the adhesive interlayer. The present study represents a new alternative modelling approach to stress analysis in the elastic joint structures. 相似文献
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O形密封圈密封性能非线性有限元数值模拟 总被引:6,自引:1,他引:5
利用ABAQUS软件建立海底采油设备用O形密封圈轴对称模型,对其在不同压缩率、不同油压时的Von Mi-ses应力及密封面接触压力分布规律进行探讨,确定O形密封圈材料易失效位置;分析压缩率和油压对O形密封圈最大Von Mises应力、最大接触压力及最大接触压与油压压差的影响。结果表明:O形密封圈最大Von Mises应力、密封面最大接触压力随压缩率和油压的增加而增加,且O形密封圈在中低高压下的密封能力高于超高下的密封能力,为海底采油设备用O形密封圈的结构设计及选型提供相关参考。 相似文献
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The contact problem of a double-layer cylindrical base is discussed with account of friction forces. The problem is reduced to an integral equation of the first kind in relation to unknown contact stresses. A direct method of collocation is used to solve it, enabling us to obtain sufficiently accurate solutions for virtually any values of the parameters. The contact stresses and the contact-zone area are calculated for various material and geometrical parameters of the base layers. 相似文献
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Swieszkowski W Bednarz P Prendergast PJ 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2003,217(1):49-57
Several studies of retrieved glenoid components from total shoulder arthroplasty show an erosion of the rim, surface irregularities, component fracture and wear resulting from polyethylene deformation in vivo. Particles resulting from polyethylene wear might be one of the reasons for the very high rate of glenoid component loosening found clinically. Because wear can be the result of high contact stresses, the aim of this study is to find out whether or not contact stresses are high enough to cause wear of the glenoid component and what influence the component type and geometry have on polyethylene contact stresses for different humerus abduction angles. Elasticity theory is used in a parametric study of contact stresses in several glenoid component designs. A finite element method is used to confirm the accuracy of the analytical solution. The analysis shows that the peak stress generated in glenoid components under conditions of normal living can be as high as 25 MPa; since this exceeds the polyethylene yield strength, wear and also cold flow of the components can be expected. It is predicted that more conforming components have lower contact stresses, which might result in lower wear rate and less cold flow. It is also found that a metal-backed component promotes higher contact stresses than an all-polyethylene component with the same total thickness, therefore it can be expected that metal-backed components have inferior wear properties. 相似文献
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为了研究关键设计参数对平面包络内啮合蜗杆传动接触性能及承载能力的影响。基于齿轮啮合原理,构建平面包络内啮合蜗杆传动的空间齿面接触线方程,利用数值计算方法求得空间齿面接触线,并将其映射到蜗轮齿面,通过分析中心距、传动比、母平面倾角、蜗轮回转轴倾角、蜗轮转角、蜗杆分度圆系数、主基圆系数等不同参数对蜗杆齿面接触区域的分布情况,找出合理的设计参数范围,此外,根据初步分析结果,选取一组较为合理参数生成了平面包络内啮合蜗杆传动的三维模型。研究表明,传动比、母平面倾角、蜗轮转角对平面包络内啮合蜗杆传动的接触区域有较大影响,母平面倾角在18°~36°、蜗轮回转中心轴倾角在30°~54°、蜗轮转角在90°~138°之间取值时,平面包络内啮合蜗杆传动的具有较好的接触区域。研究结果为平面包络内啮合蜗杆传动的后续研究奠定了理论基础。 相似文献
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采用摩擦磨损试验机,获得了QAL9-4/40Cr和ZCuAl8Mn13Fe3/40Cr两种闸门底枢摩擦副在不同接触应力的脂润滑条件下的摩擦学特性,并运用灰色系统理论GM(1,1)模型对其达到许用磨损量的磨损失效进行了评价。低速重载条件下,两种摩擦副的实际接触应力在许用应力之下时,其磨损形式均以犁切为主,且磨损量随接触应力的增大而增大,摩擦因数随着接触应力的增大而减小;反之,其磨损形式均以黏着为主,且磨损速度、摩擦因数均会急剧增加。受同一接触应力作用时,QAL9-4/40Cr具有更好的耐磨性。理论模型对磨损失效的预测结果与实测值吻合度达到95%。 相似文献