基于COSMOSMotion的偏心齿轮机构运动仿真

介绍了三维机械设计软件SolidWorks及其二次开发,并基于SolidWorks建立了偏心齿轮变速机构的实体模型,运用COSMOSMotion对其进行了运动仿真,得出相应的运动曲线,将以电子表格形式存放的动画模拟数据和理论分析数据做了一定的对比和分析,提高机构设计的直观性.     

偏心渐开线齿轮在高速包装机上的应用

采用偏心渐开线齿轮传动作为高速包装机横封机构，与其它变速传动机构相比，这种机构不仅结构简单，拆装方便，而且速度变化范围较大，传动较平稳，容易进行动平衡。从而能较好地改善封头和切刀的寿命。它最诱人的优点是容易制成可调变速范围的结构，以慢适应不同的物料和包装材料，并且它的制造成本非常低，与普通齿轮传动的制造成本几乎相同。     

偏心渐开线齿轮在高速包装机上的应用

采用偏心渐开线齿轮传动作为高速包装机横封机构，与其它变速传动机构相比，这种机构不仅结构简单，拆装方便；而且速度变化范围较大，传动较平稳，容易进行动平衡，从而能较好地改善封头和切刀的寿命，它最诱人的优点是容易制成可调变速范围的结构，以便适应不同的物料和包装材料，并且它的制作成本非常低，与普通齿轮传动的制造成本几乎相同。     

混合齿轮行星系分插机构的设计与仿真

将偏心齿轮-非圆齿轮行星系应用于插秧机分插机构中,研制出混合齿轮行星系分插机构.建立偏心齿轮与非圆齿轮的节曲线数学模型,获取齿轮节曲线方程,并结合KISSSOFT和MATLAB软件对非圆齿轮进行设计.建立分插机构运动数学模型,利用MATLAB开发优化辅助软件,对分插机构的参数进行优化.完成了分插机构的三维CAD设计,并在ADAMS中对分插机构进行了运动学虚拟仿真,获取了秧针尖点的静态轨迹和动态轨迹,将其与理论分析得到的轨迹曲线进行对比,验证了混合齿轮行星系应用于插秧机分插机构上的可行性.     

一种汽车门锁塑料齿轮机构设计优化

汽车门锁传动机构中的齿轮是自吸合汽车门锁系统中容易失效的部件,对汽车的行驶安全起着重要影响。近年来,在汽车行业的电装产品中,塑料齿轮逐渐替代一些金属齿轮。为了保证汽车门锁传动机构中的塑料齿轮能够可靠稳定的工作,满足其工作强度要求,本文介绍了一种基于尼曼温特尔法与刘易斯疲劳强度理论的塑料齿轮强度计算方法,提出了提高齿轮强度,优化塑料齿轮传动性能的设计方法。经过优化设计后,塑料齿轮性能得到提升并能够正常工作,证明了齿轮优化设计是成功的。     

基于齿轮传动系统横-扭-摆耦合非线性动力学模型的齿廓修形优化设计

基于齿轮传动系统动力学模型的齿廓修形优化设计可真实地反映修形参数对齿轮动态特性的影响。考虑几何偏心、陀螺力矩和齿向偏载力矩,建立了单级齿轮传动系统10自由度横-扭-摆耦合非线性动力学模型。提出了考虑齿轮实际运动状态并可适用于齿廓修形齿轮的啮合刚度模型,并采用解析法计算啮合刚度。为了降低齿轮传动系统的振动和噪声,以减小齿轮传动系统的动载系数为目标,建立了基于齿轮传动系统横-扭-摆耦合非线性动力学模型的齿廓修形优化模型。对某重载车辆齿轮传动系统进行了齿廓修形优化设计,优化结果有效的降低了齿轮的动载荷,可为设计低振动和低噪声的齿轮传动系统提供依据。     

齿轮传动式百分表示值误差的分析

百分表是利用精密齿条齿轮机构制成的表式通用长度测量工具,由于使用频繁易发生示值超差不合格,本文通过分析设计结构和齿轮变形等几方面值确定误差的几个方面:齿形误差、齿轮偏心误差、刻度盘偏心误差和齿轮周节的累积误差。     

一种傅里叶非圆齿轮驱动的横封机构设计

目的设计一种符合块状包装物横封要求的横封机构,以更好满足横封的工艺要求。方法在分析块状物体横封工艺过程基础上建立傅里叶非圆齿轮数学模型,根据工艺要求建立目标函数以及横封机构参数优化模型,并通过实例进行验证。结果通过实例计算可知,优化设计得到的傅里叶非圆齿轮能更好满足设计要求,比原有传统偏心圆具有更高的灵活性。结论采用更加灵活的傅里叶非圆齿轮副驱动横封机构对横封机构参数进行优化设计,能够更好地满足块状物体横封工艺要求。     

星轮偏心误差对浮动式星型齿轮传动动态特性的影响

以太阳轮浮动式星型齿轮传动系统为研究对象,基于集中参数理论,建立了星型传动广义动力学模型,建模中考虑了齿轮制造偏心误差、时变啮合刚度以及间隙浮动机构等因素。采用数值解法对系统的动力学微分方程进行求解,获得了系统的受迫振动响应,利用时间历程、相平面、Poincare截面图及Fourier频谱分析了系统的动态特性。着重研究各星轮偏心误差及间隙浮动机构对星型轮系动态特性的影响规律。结果表明:星轮偏心误差增强了系统振动;不同位置、不同数量的星轮偏心误差作用,对应的系统动态响应不同;间隙浮动结构影响了系统的稳定性,不利于振动噪声的控制。     

单张纸输送装置变速机构的运动分析

地单张纸输送装置中的变速机构－－齿轮连杆机构进行了运动分析,编制了其通用计算程序。     

纸机旋转空心铸钢辊的弹性分析及其应用

研究了考虑离心力(设计车速)影响时高速纸机中具有闷头的空心铸钢辊结构的强度计算和优化设计问题。应用弹性理论导出了配合压力的一般公式,根据等强度设计思想,建立了辊筒与闷头中的最大Tresca等效应力的计算公式,进而提出了最优过盈量的计算方法,算例针对某设计车速给出了可用于铸钢辊结构优化设计的曲线图。分析方法和解析解对于工程中其它由塑性材料制成的旋转双重过盈配合结构的强度计算和优化设计也有参考价值。     

A numerical study on the optimal geometric design of speed control humps

The aim of the present paper is to find an optimum speed control hump geometric design by using the sequential quadratic programming method. Theoretical investigation of the dynamic behavior of the driver body components and the vehicle due to crossing speed control humps is presented. The vehicle–driver system represented as a mathematical model consists of 12 degrees of freedom (DOF). Seven DOFs are used for the human body model in the heave mode and the rest are for the vehicle body, suspension system and tires. An optimum design method for the hump geometry is proposed to reduce the excessive shocks experienced by drivers when crossing the hump below the speed limit, while being unpleasant when going over the speed limit. The pleasant or unpleasant ride, or what is called comfort criteria (CC), is modeled by calculating the driver's head acceleration. In this regard, the geometry of the hump will be controlled to match an optimum practical shape that can be implemented economically. Three types of humps are discussed and evaluated in the optimization technique. These humps are Watts, flat-topped and polynomial humps. For Watts and flat-topped humps, different rise and return profiles which are used as design variables, are sinusoidal, harmonic, cycloidal, circular and modified harmonic. The global design was selected from 42 optimal designs which are found by combining different rise/return profiles for the three types of humps. The effect of special cases such as symmetrical roads, design limitations, CC, critical speed (CS) and system parametric variations on the optimal design of speed control humps are presented at the end of this paper.     

Vibration and optimum design of rotating laminated blades

The vibration and optimum design of a rotating laminated blade subject to constraints on the dynamic behavior are investigated. Restrictions on multiple natural frequencies as well as the maximum dynamic deflections of rotating laminated blades are considered as constraints on the dynamic behavior of the system. Aerodynamic forces acting on the blade are simulated as harmonic excitations. The optimality criterion method and the modified method of feasible directions have been successfully developed for optimizing the weight of the rotating laminated blade. Effects of radius of the disk, aspect ratio, and rotating speed on the system dynamic behaviors and/or the optimum design are also studied. The vibration analysis shows that most of the bending modes can be significantly affected by the rotating speed and the radius of the disk. Results also show that the optimum weight with constraints on the dynamic response is higher than that with frequency constraints. Moreover, results show that the weight of the rotating laminated blade can be greatly reduced at the optimum design stage.     

Mixed-flow vertical tubular hydraulic turbine: determination of proper design duty point

A new vertical single-regulated mixed-flow turbine with conical guide apparatus and without spiral casing is presented in this paper. Runner blades are fixed to the hub and runner band and resemble to the Francis type runner of extremely high specific speed. Due to lack of information and guidelines for the design of a new turbine, a theoretical model was developed in order to determinate the design duty point, i.e. to determine the optimum narrow operation range of the turbine. It is not necessary to know the kinematic conditions at the runner inlet, but only general information on the geometry of turbine flow-passage, meridional contour of the runner and blading, the number of blades and the turbine speed of rotation. The model is based on the integral tangential lift coefficient, which is the average value over the entire runner blading. The results are calculated for the lift coefficient 0.5 and 0.6, for the flow coefficient range from 0.2 to 0.36, for the number of the blades between 5 and 13, and are finally presented in the Cordier diagram (specific speed vs. specific diameter). Calculated results of the turbine optimum operation in Cordier diagram correspond very well to the adequate area of Kaplan turbines with medium and low specific speed and extends into the area of Francis turbines with high specific speed. Presented model clearly highlights the parameters that affect specific load of the runner blade row and therefore the optimum turbine operation (discharge—turbine head). The presented method is not limited to a specific reaction type of the hydraulic turbine. The method can therefore be applied to a wide range from mixed-flow (radial-axial) turbines to the axial turbines. Applicability of the method may be considered as a tool in the first stage of the turbine design i.e. when designing the meridional geometry and selecting the number of blades according to calculated operating point. Geometric and energy parameters are generally defined to an extent that these parameters are considered in detailed design using turbulent viscous flow CFD solver.     

低温高速离心泵的研制与应用

阐述了适合于输送低温介质的高速离心泵的水力设计和结构设计方法，结构上采有长，中，短叶片相间的复合叶轮及双密封结构，理论上采用以效率为目标函数的优化水力设计方法，保证了低温高速离心泵具有很好的工人可靠性和优越的性能指标。     

Optimization of microstructural and mechanical properties of friction stir welding using the cellular automaton and Taguchi method

In this study, microstructural and mechanical properties of friction stir welding (FSW) of AA1100 is optimized using Taguchi L9 orthogonal design of experiments. First, in order to study the microstructural properties of the weld, microstructure evolution of the weld zone is simulated with the cellular automaton (CA) method coupling the modified Laasraoui–Jonas (LJ) model. Then, the microstructural simulation results were validated by obtained experimental results. Good agreements between the simulation and the experimental results were observed. Then, tensile and hardness test were done to investigate the mechanical properties of the weld. The design parameters considered in the experiment were rotational speed, traverse speed, and shoulder diameter. The optimum process parameters were determined with reference to grain size (GS), ultimate tensile strength (UTS) and hardness. The predicted optimal value of grain size, ultimate tensile strength and hardness was validated by conducting the confirmation test using optimum parameters. Analysis of variance was done in order to determine the most dominant factors in friction stir welding.     

On designing of flywheels for electromechanical plants

The optimum design of a rotating axially symmetric disk (flywheel) under geometric and strength constraints is examined. As a function of the radial coordinate, the disk thickness should be so selected that a kinetic energy maximum is facilitated for the given rotational speed. This piecewise continuous function constrained from above is determined numerically. The method of penalty functions is used for solving the problem of search for the conditional maximum. The effect of geometrical design constraints on the optimum form of the disk is analyzed.Translated from Problemy Prochnosti, No. 3, pp. 85–88, March, 1991.     

高层钢结构TMDs风振舒适度控制最优参数与简化设计

分别将脉动风视为白噪声和采用Davenport风速谱，基于建筑荷载规范GBJ9－87，导出了高层钢结构－TMD系统减振系数DRF1和DRF2。数值研究表明；高层钢结构的基本周期和基本风压不影响TMDs最优设计参数；将脉动风设为白噪声或采用Davenport风速谱时，TMDs最优设计参数未有改变，但减振系数略有变化。同时，基于导出的高层钢结构TMD－系列加速度传递函数及加速度动力放大系数，研究了TMDs最优参数取值。提出了高层钢结构TMD风振舒适度控制简化设计过程。数值算例说明了本文方法的应用及TMDs对高层钢结构风振舒适度控制的有效性。比较了基于位移和加速度设计的TMDs系统。     

低比转速高速液氮离心泵的设计与试验研究

以比转速为43的高速液氮离心泵为例阐述了低温高速离心泵的结构设计和水力设计方法。结构上采用金属波纹管密封和聚氨脂同步齿形带传动等结构形式，理论上采用水中短叶片相间的复合叶轮优化设计方法，水力试验和现场应用表明，提出了结构方案和设计方法合理可行。     

挂壁式空调器室内机风量、噪声及功率变化规律研究与应用

通过对科龙4款具有代表性的不同结构挂壁式空调器室内机的试验研究,得出挂壁式空调器室内机的风量、噪声、功率随转速变化的规律,拟合出其所遵循的函数方程,提出一种简单的室内机风量、噪声、功率的优化设计方法.