齿轮在复合啮合下的偏载计算

齿轮在复合啮合下的偏载计算包头钢铁学院（０１４０１０）刘鹄然复合啮合是指两个以上齿轮的啮合。如图１所示，当轮２驱动轮１和轮３，根据文献对于轮１和轮３依然有ｄ２ψ１ｄｘ２＝ｒ１ｐ１２ｃｏｓα／Ｇ１Ｊ１（１）ｄ２ψ３ｄｘ２＝ｒ３ｐ２３ｃｏｓα／Ｇ３Ｊ３（...     

在滚齿机上加工小螺旋角齿轮的方法

在仪器和精密机械中经常采用蜗杆——斜齿轮传动来获得较大的传动比。用于这种传动的斜齿轮齿数较多、螺旋角较小、用通常方法加工常因其差动挂轮比过小,挂轮困难而不能实现,现根据我们的经验介绍两种加工方法供参考。一、无差动调整法无差动调整法可避免使用差动挂轮。其分度与进给挂轮的计算公式如下:式中C分、C进为机床分度和进给常数,Z_1为     

在滚齿机上加工斜齿轮时挂轮的微机辅助选择

该文介绍了一种在滚齿机上加工斜齿轮时利用计算机选择分齿挂轮与差动挂轮齿数的方法,只要将斜齿轮的齿数、法向模数、分度圆螺旋角、滚刀头数输入计算机选择分齿挂轮与差动挂轮齿数的方法,只要将斜齿轮的齿数、法向模数、分度圆螺旋角、滚刀头数输入计算机,立即就能得出分齿挂轮与差动挂轮的齿数,这种选择方法速度快、精度高、使用方便.     

在滚齿机上加工斜齿轮时挂轮的微机辅助选择

该文介绍了一种在滚齿机上加工斜齿轮时利用计算机选择分齿挂轮与差动挂轮齿数的方法，只要将斜齿轮的齿数、法向模数、分度圆螺旋角、滚刀头数输入计算机选择分齿挂轮与差动挂轮齿数的方法，只要将斜齿轮的齿数、法向模数、分度圆螺旋角、滚刀头数输入计算机，立即就能得出分齿挂轮与差动挂轮的齿数，这种选择方法速度快、精度高、使用方便。     

滚切变位齿轮时滚刀安装角

在滚切变位齿轮时,滚刀安装角的调整在生产实践中是不可忽视的。尤其是用标准滚齿刀切削模数和变位系数较大,精度8～7级的齿轮时,如果滚刀安装角误差过大,就会明显的影响齿形精度。在滚切齿轮时,必须保证滚刀刀齿的运动方向和齿轮的齿向一致,螺旋升角λ=arc sin m/α_2,滚切标准齿轮时,滚刀的分度圆与齿轮的分度圆相切,两者的分度圆成为切削节圆,分度圆与节圆重合(图1α),对于标准直齿轮,滚刀安装角θ=λ(滚刀螺旋角)。对于标     

无差动法滚切斜齿圆柱齿轮挂轮的精度分析

1.无差动法滚切斜齿圆柱齿轮原理 应用无差动法在滚齿机上滚切斜齿圆柱齿轮时,不论齿数多少,分度挂轮传动比均为: i_1=A_1K/Z(?)ssinβ/m_nπ(1) 式中 m_n——齿轮工件法向模数,mm β——齿轮工件分度圆螺旋角,(°) z——齿轮工件齿轮 K——滚刀头数 A_1——机床分齿挂轮定数 s——机床轴向进给量,mm/r 式(1)中符号的规定如下表所示。 2.误差计算式 由于式(1)中包含有无理数,故分齿挂轮传动比只能是近似的,i_1的误差势必对β角产生影响。另外,轴向进给量8是由进给挂轮决定的,若进给挂轮传动比有误差,即8有误差,也会造成β角的误差。     

用万能铣加工质数斜齿轮

在设备维修中,常有急需更换齿轮的情况,当遇到直齿齿轮时,一般铣床就能加工,但是斜齿轮加工就较困难。若齿数能够用单式分度法进行分度,再根据导程计算挂轮,尚可铣削。若齿数为质数,则不能用单式分度法,只能用复式分度或差动分度(?),而后者又必须在分度头上加装挂轮装置。但由于是加工斜齿轮,挂轮装置又必须用于转动工件的螺旋转动,一套     

准双曲面齿轮刀倾全展成切齿调整计算方法

利用变性全展成法(HGM-D法,详见文献[1])加工准双曲面齿轮,由于刀盘轴线与摇台轴线平行,得到的大轮根锥压力角与刀具齿形角相同。当刀具齿形角与要求的大轮根锥压力角相差较大时,需要在有刀倾机构的铣齿机上用刀倾全展成法(简称HGT法)加工大齿轮。美国Gleason公司的HGT法,为简化计算把小轮切齿调整计算基准点选在大轮分度锥面上齿槽中部齿圈中点P_2处,由于计算基准与齿面接触区中心对应点M_2不重合,理论上存在误差,切齿时得不到图纸要求的接触区。为了把齿面接触区移到要求的位置,不得不根据实际接触印痕进行附加调整。本文提出的HGT-D法,可选与大轮齿面对应的任一点(一般为接触区中心对应点M_2)为小轮切齿调整计算基准,消除了理论误差,可以加速切齿调整和提高齿轮啮合质量。     

校核挂轮啮合的几何分析法

在机械加工中,例如车制螺纹、铣螺旋线或斜齿轮,以及铣床分度头差动分度、齿轮加工机床的分度,都需选配挂轮。因此,计算挂轮的工作量较大。选配的方法繁杂,为简化挂轮计算和缩短选配时间,现介绍校核挂轮啮合的几何分析法供参考。     

一种简单准确的斜齿轮螺旋角测算方法

介绍的斜齿轮螺旋角测绘方法不涉及斜齿轮变位系数、法向压力角和齿顶圆直径,仅用通用量具对斜齿轮进行测算求得分度圆螺旋角;并推导了求解分度圆螺旋角公式.该方法简便易行、准确可靠.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.