Analysis of the Meshing of Crown Gear Coupling

This paper presents an analysis result of three-dimensional meshing of crown gear coupling （CGC） surfaces of crown gear and internal gear are established. The equation of internal gear surface is given. The equation of conjugate surface of crown gear is solved according to the principle of gearing, and that of non-conjugate crown gear is derived with crown curve of a circular arc. The meshing state of conjugate and non-conjugate surfaces is analyzed through computation of contact lines and points. It is concluded that the meshing of conjugate CGC is line-contact, there are several pairs of teeth engage simultaneously, and non-conjugate CGC has point-contact condition of meshing and only 2 pairs of teeth engage in theory.

Dynamic Simulation for Rigid-Flexible Coupling Model of Gear Transmission System Based on ADAMS

The influence of the flexible body for the motion of gear transmission system is analyzed and the foundation for a more accurate assessment of gear transmission system is established when it has battle damage faults. By using Pro / E software,the virtual prototype model of gear transmission system in the speed reducer is established,and the rigid model and rigid-flexible coupling model are simulated respectively in ADAMS to obtain the data of gear meshing force. It can be concluded that rigid-flexible coupling model can reflect the real motion better than rigid model by comparing the simulation data of two models.

Dynamic response of large increased pressure wind tunnel rotor-gear coupling system with parallel misalignment

To study the misalignment of gear coupling, this paper analyzed the distortion of the tooth of gear coupling on the base of gear coupling’s motion under parallel misalignment, and derived the specific expression of additive radial force, which produced by the rotor’ torque. The motion differential equations of the large increased pressure wind tunnel rotor-gear coupling system were derived by the finite element method. Newmark integral method was applied to calculate the dynamic response of the system with parallel misalignment. The numerical results show that: under the effect of additive radial force, the static misalignment can arouse 2X frequency component lateral vibration; the dynamic misalignment can arouse2X,4X,6X multiple frequency components lateral vibration. The 2X frequency component is obvious. The additive radial force of the gear coupling can arouse lateral vibration with even multiple frequency components.

Bifurcation and chaos study on transverse-torsional coupled 2K-H planetary gear train with multiple clearances

A new non-linear transverse-torsional coupled model was proposed for 2K-H planetary gear train, and gear's geometric eccentricity error, comprehensive transmission error, time-varying meshing stiffness, sun-planet and planet-ring gear pair's backlashes and sun gear's bearing clearance were taken into consideration. The solution of differential governing equation of motion was solved by applying variable step-size Runge-Kutta numerical integration method. The system motion state was investigated systematically and qualitatively, and exhibited diverse characteristics of bifurcation and chaos as well as non-linear behavior under different bifurcation parameters including meshing frequency, sun-planet backlash, planet-ring backlash and sun gear's bearing clearance. Analysis results show that the increasing damping could suppress the region of chaotic motion and improve the system's stability significantly. The route of crisis to chaotic motion was observed under the bifurcation parameter of meshing frequency. However, the routes of period doubling and crisis to chaos were identified under the bifurcation parameter of sun-planet backlash; besides, several different types of routes to chaos were observed and coexisted under the bifurcation parameter of planet-ring backlash including period doubling, Hopf bifurcation, 3T-periodic channel and crisis. Additionally, planet-ring backlash generated a strong coupling effect to system's non-linear behavior while the sun gear's bearing clearance produced weak coupling effect. Finally, quasi-periodic motion could be found under all above–mentioned bifurcation parameters and closely associated with the 3T-periodic motion.

Coupled lateral-torsional-axial vibrations of a helical gear-rotor-bearing system

Considering the axial and radial loads, a math- ematical model of angular contact ball bearing is deduced with Hertz contact theory. With the coupling effects of lateral, torsional and axial vibrations taken into account, a lumped-parameter nonlinear dynamic model of helical gearrotor-bearing system （HGRBS） is established to obtain the transmission system dynamic response to the changes of dif- ferent parameters. The vibration differential equations of the drive system are derived through the Lagrange equation, which considers the kinetic and potential energies, the dis- sipative function and the internal/external excitation. Based on the Runge-Kutta numerical method, the dynamics of the HGRBS is investigated, which describes vibration properties of HGRBS more comprehensively. The results show that the vibration amplitudes have obvious fluctuation, and the frequency multiplication and random frequency components become increasingly obvious with changing rotational speed and eccentricity at gear and bearing positions. Axial vibration of the HGRBS also has some fluctuations. The bearing has self-variable stiffness frequency, which should be avoided in engineering design. In addition, the bearing clearance needs little attention due to its slightly discernible effect on vibration response. It is suggested that a careful examination should be made in modelling the nonlinear dynamic behavior of a helical gear-rotor-bearing system.

Nonlinear Dynamic Analysis of Coupled Gear-Rotor-Bearing System with the Effect of Internal and External Excitations

Extensive studies on nonlinear dynamics of gear systems with internal excitation or external excitation respectively have been carried out. However, the nonlinear characteristics of gear systems under combined internal and external excitations are scarcely investigated. An eight-degree-of-freedom（8-DOF） nonlinear spur gear-rotor-bearing model, which contains backlash, transmission error, eccentricity, gravity and input/output torque, is established, and the coupled lateral-torsional vibration characteristics are studied. Based on the equations of motion, the coupled spur gear-rotor-bearing system（SGRBS） is investigated using the Runge-Kutta numerical method, and the effects of rotational speed, error fluctuation and load fluctuation on the dynamic responses are explored. The results show that a diverse range of nonlinear dynamic characteristics such as periodic motion, quasi-periodic motion, chaotic behaviors and impacts exhibited in the system are strongly attributed to the interaction between internal and external excitations. Significantly, the changing rotational speed could effectively control the vibration of the system. Vibration level increases with the increasing error fluctuation. Whereas the load fluctuation has an influence on the nonlinear dynamic characteristics and the increasing excitation force amplitude makes the vibration amplitude increase, the chaotic motion may be restricted. The proposed model and numerical results can be used for diagnosis of faults and vibration control of practical SGRBS.

Bending-Torsional Coupled Vibration Test of Large Power Gear Transmission System

In order to test the bending-torsional coupled vibration characteristics of the multi-shafts gear transmission system of large power vehicles,a torsional vibration exciter was used to apply torsional excitation on the gear transmission systems and thirty-two acceleration sensors were used to measure the tangential acceleration of each shaft.Torsional vibration signals and bending vibration signals of each measuring point were obtained by calculation of the four-point-response signal.The modal parameters of gear transmission systems including nature frequency,modal shape and modal damping ratio were obtained by identifying modal parameters of the torsional vibration signal and bending vibration signal.The characteristic of the bending vibration and torsional vibration of the gear systems were studied through the analysis of the nature frequency and modal shape.The nonlinearity characteristic of the gear transmission system was investigated through single frequency excitation test,which can be the foundation for further nonlinearity research.

Modeling and Simulation of Power Coupling System in Hydraulic Hybrid City Bus

In order to solve the coupling problem of power in Hydraulic Hybrid City Bus (HHB), a hydraulic hybrid power coupling system based on planetary gear transmission principle is proposed in this paper. The system consists of diesel engine, power coupler, hydraulic pump/motor, etc. The realizable operating modes of power coupling system are analyzed in this paper. Under coordination of clutches, the engine driven mode, hydraulic driven mode, hybrid driven mode, hydraulic engine-start mode and braking energy recovery mode are realizable. Based on Lagrange equation, kinetic analysis and kinematics analyses are presented. In addition, the simulation model of the power coupling system is proposed, which includes diesel engine model, power coupler model, hydraulic pump/motor model, etc. The example simulation analysis is proposed under the hybrid driven mode;the results show that the power coupling system proposed in this paper can realize power coupling of hydraulic hybrid city bus. Compared with traditional city bus, the hydraulic hybrid city bus can choose small-displacement engine so as to improve fuel economy and dynamic property.

Coupling for Parallel Non-Collinear Shafts

A novel coupling for two parallel shafts with non-collinear axes has been developed and used in a cycloidal transmission with magnetic gears. Such a coupling has been designed as an alternative to traditional couplings to transmit the rotation from the orbiting gear to the output shaft. The driving shaft transmits a couple consisting of two equal and opposite forces to a central element which, in turn, transmits the same couple, also consisting of two equal and opposite forces to the driven shaft. This novel coupling was successfully used instead of a traditional coupling resulting in, not only a smother operation, but also a more efficient power transmission.

FINITE ELEMENT SOLUTION TO COUPLED THERMO－ELASTICCONTACT STRESS AND IMPACTRESPONSE OF MESHING GEARS

A mixed finite element solution of contact stresses in meshing gears is investigated with the consideration of coupled thermo-elastic deformation and impact behavior. A simulation procedure of finite element solution of meshing gears is developed. The versatility of the procedure for both numerical accuracy and computational efficiency is verified by numerical analysis of meshing gear teeth.

全齿轮耦合机器人齿侧间隙建模与公差仿真

鉴于全齿轮耦合机器人齿轮传动链长、反转频率高的特点,分析机器人的结构和传动原理.为了减小侧隙对机器人传动精度的影响,提出齿侧间隙理论建模及三维公差仿真分析方法.针对驱动端的圆柱齿轮机构,对齿侧间隙进行理论建模和公差仿真分析,两者相吻合.针对关节处的圆锥齿轮机构,提出将圆锥齿轮副等效为假想圆柱齿轮副的侧隙建模方法,与公差仿真分析结果吻合.以机器人肩关节偏摆传动链为分析对象计算机器人末端误差,为了降低齿侧间隙及其导致的传动链回程误差,提出圆锥齿轮加垫的计算方法和电机转角补偿方法,通过实验验证该补偿方法的有效性.

一种零泄漏的齿轮泵设计

介绍了齿轮泵的设计过程,从变位系数和压力角两个方面着手,重点阐述了依据排量和中心距设计齿轮参数的选择方法。为实现零泄露,采用了磁性联轴器代替机械密封,结构更紧凑,密封性更好。齿轮泵整体结构小巧,能满足实际需求。

高温超导磁力传动的发展现状及前景

鉴于高温超导材料具有高载流、强捕获磁场特性与迈斯纳效应,将高温超导材料应用于磁力传动装置,可在实现无接触转矩传输的同时,显著提高转矩密度、传动效率等性能。国内外已开展高温超导磁力传动的理论与应用研究工作,并取得了相应的进展。以高温超导磁力耦合器和高温超导磁齿轮为研究对象,通过调研国内外相关文献,从结构及原理、建模与分析两方面综述高温超导材料在磁力传动领域的研究现状。在此研究基础上,进一步探讨高温超导磁力传动研究在创新拓扑结构设计、冷却与供电、超导磁体交流损耗、复杂传输特性的多目标优化所面临的问题及未来发展前景。

齿轨车辆牵引电机布置模式及系统耦合振动特性

为探究牵引电机布置模式对齿轨车辆动态特性及齿轮-齿轨啮合特性的影响,在考虑齿轮-齿轨非线性啮合行为及其动态时变激扰和轮轨非线性接触关系的条件下,分析了不同电机布置模式下的车辆动力学特性。以Strub齿轨系统为原型,建立了齿轨车辆-轨道垂纵耦合动力学模型,研究了三种不同电机驱动形式对齿轨车辆动态特性的影响规律,并在此基础上提出了适用于齿轨车辆的牵引电机布置方案。研究表明:牵引电机双置工况下齿轮啮合力和垂向、纵向振动加速度更小;其中电机双置时齿轮齿轨啮合力约为电机后置和前置时的50%,平直段齿轮垂向和纵向加速度的最大幅值差分别为4.04和6.01 m/s^(2),爬坡段电机后置时齿轮振动加速度最大,其垂向、纵向加速度幅值比电机双置时大45%;平直线路上电机后置与前置时齿轨车辆的舒适性较好,而爬坡段牵引电机双置模式下更好;鉴于齿轨车辆主要应用于爬坡线路,且爬坡时电机双置齿轨车辆的动力学指标最好,因此建议牵引电机双置为最优布置模式。

考虑多场耦合作用的航空薄辐板齿轮热处理后辐板车削变形研究

薄辐板齿轮拥有质量轻、结构与受力相匹配等诸多优点,常应用于航空航天等重要场合。然而,薄辐板齿轮本身的刚度较小,工艺过程复杂且涉及应力场、温度场等多个物理场的耦合作用,难以对其进行精确变形及加工精度的控制与预测。以薄辐板齿轮件为研究对象,针对齿轮辐板的热处理及车削加工工艺过程,建立了零件的工艺参数与其应力场间的映射模型,并通过试验验证了该模型的正确性;基于该模型,分析了不同的工艺参数、工艺路线以及零件的装夹方式等对航空薄辐板齿轮辐板的热处理后车削加工变形的影响,明确并优化了导致零件产生变形的主要因素。

SGZ1000/2×1200刮板输送机链轮轴组改造设计

链轮轴组是煤矿井下输送设备不可或缺的部件,刮板输送机、转载机的链轮轴组在工作面使用过程中出现故障需要更换时,必须先将输送设备动力部拆下后才可更换,耗费大量的人力、物力及时间。为解决这一问题,设计出一种可快速拆解式的链轮轴组,将链轮轴组与减速器的直接联接方式进行改进,通过一种齿轮联轴器进行互联,既能实现轴组与减速器的联接,也能实现轴组的快速更换。

预选挡对双离合变速器敲击动力学影响的试验研究

搭建可模拟发动机转速波动的变速器敲击动力学试验台架,采集双离合变速器(dual-clutch transmission, DCT)的壳体振动和齿轮瞬时转速信号,研究不同预选挡位下DCT变速器的敲击响应和齿轮系统动力学随输入角加速度幅值变化的演变规律。根据齿轮系统间隙非线性动力学模型的计算结果和齿轮啮合基本定律,提出了一种基于齿轮特征频率角加速度幅值特性的齿轮运动状态判定准则。台架敲击试验结果表明预选挡显著改变DCT变速器的敲击响应和齿轮副动力学行为,当输入角加速度幅值增加到某一数值时,DCT变速器敲击响应发生向上跳跃现象,主动和被动子变速器之间产生明显的低频动力学耦合,承载齿轮转速信号呈现显著的多谐波非线性特性。根据提出的齿轮运动状态判定准则判断跳跃突变后的承载齿轮副发生齿面分离和敲击现象,动力学突变后的动力学耦合导致DCT变速器的敲击响应急剧恶化。最后,在整车上验证了台架试验的动力学耦合和敲击响应突变现象。

稳态工况下电机-齿轮系统机电耦合动态特性研究

针对由永磁同步电机和一级斜齿轮减速器组成的传动系统进行了研究。建立了永磁同步电机模型和一级斜齿轮动力学模型联合的机电耦合动力学模型。在施加恒定转速和恒定负载条件下,分析了机电耦合传动系统的电信号动态响应。通过研究,发现定子电流和电磁转矩含有反映齿轮啮合频率的信息,并且相比与电磁转矩,定子电流含有的传动系统频率信息更加丰富,这表明机械系统的频率会和电气系统中的定子电流和电磁转矩频率产生调制。证明电机的电气性能会受到机械系统特性的影响,研究结果为通过定子电流及其相关参数进行机电耦合系统的动态性能监测和故障诊断这一研究方法提供了参考,在此基础上,可以展开更深入的研究。

综掘机截割部混合动力系统的设计与仿真分析

为解决综掘机传动动力传动系统在遇到煤岩条件突变工况时对系统零部件冲击较大且能量利用率低的问题,提出了混合动力传动系统的总体方案,并根据实际工况具体设计了液压系统中蓄能器和液压马达的选型,机械系统中扭矩耦合齿轮的参数;基于AMESim软件对混合动力传动系统的性能进行了验证,达到了预期的效果。

热镀锌机组矫直机压下装置故障原因分析及改进

分析了邯钢邯宝冷轧厂热镀锌机组矫直机常见的压下调节装置主轴断裂、蜗轮蜗杆同步轴两端不平衡等问题,采取了有针对性的改进措施,解决了矫直机压下调节装置同步轴主轴断裂、故障无法及时发现造成事故扩大化等问题,创造了可观的经济效益,有效地保证了生产线的稳定运行。