共查询到20条相似文献,搜索用时 31 毫秒
1.
A dynamic model of transmission system for a marine gear is established considering time-varying mesh stiffness, mesh damping and tooth composite error. The solution efficiency is improved by taking contact line length change of gear pair instead of instantaneous gear mesh stiffness change and making mesh damping and tooth surface equivalent to viscous damping. Multi-objective dynamic optimization design is put into practice to improve the marine gear transmission system using vibration acceleration and mass as target function. The results show that the optimization method can effectively reduce the vibration level and mass of marine gear. 相似文献
2.
For a ISA HEV,the transmission gear shaft dynamic model is established and the 3-D modal analysis is carfled out. Based on above work, the structure of the gear shaft is analysed, then the diameter of the gear shaft is taken as a design variable. With first order optimization,low inherent frequencies are optimized in order to avoid resonance and decrease NVH. 相似文献
3.
The differential equation which governs the behavior of the gear transmission system of 1.5 MW wind turbine is established. The external excitation caused by wind speed fluctuation is discussed and the internal excitation due to time varying mesh stiffness and comprehensive error is also analyzed. The calculating formulations of the harmonic balance method of nonlinear dynamic equations are presented. Then, the multi objective dynamic optimization model is developed to minimize the value of vibration acceleration and the overall volume. The optimization of a practical example using mixed discrete combined programming is performed. The result shows that the proposed method of modeling and optimization design can effectively reduce the wind turbines gearbox vibration levels and weight. 相似文献
4.
Zhu Caichao Qin Datong LiRunfang Cheng Zongyuan 《保鲜与加工》1997,(2):89-94
The epicyclic gear drive with internal tooth has been analysed,the formula has been also deduced for computing the inertial force and change of contact force,and the dynamic optimization of system parameters for the force of bearing has been carried,it has given a reliable proof to reduce the dynamic load and prolong the life of bearing of three ring type reducer. 相似文献
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This research investigated problems influencing tracked vehicles steering dynamic characteristics, such as rolling resistance during straight driving, steering centrifugal resistance, acceleration resistance during straight driving, scratching soil resistance of steering. Based on research about the relationship between the hydraulic steering regulation speed system and its maximum stable work pressure when vehicles have central steering on good roads (such as cement and rural roads), a zero differential hydraulic steering system of power shift steering transmission can ensure that vehicles maintain straight ahead stability through reasonably matching a steering drive system. The test indicates that vehicles have good dynamic characteristics when the work pressure accounted for 60% to 80% of the security work pressure. 相似文献
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Thetraditional power steering by fluid drive has many defects such as producing extra steering, oil pollution and consuming excessive resources. Electric Power Steering is servo-control system which can supply power by motor which is controlledby micro-processor-embeded controller. So the application of Electric Power Steering Systemin vehicleis the developing direction. Based on the deep research of power steering system for vehicle, aiming at the complexity and uncertaintyof road and the difference for driver operating habit, the paper presents a sort of new algorithmthat is stronger in robustness, better in adaptability. The algorithmhas been applied in the physical vehicle steering system. The engineering practice shows that the algorithmtakes care of both control effect and person's feeling, and it is satisfactory to control effect. 相似文献
7.
Taking the sliding bearing into account, the lateral vibration analysis models of two single rotor were built respectively using the transfer matrix method. The transmission matrix of herringbone gear coupled unit is derived. Using whole transfer matrix method, the lateral torsional coupling analysis model of herringbone gear rotor system is set up, and the vibration characteristics of gear rotor bearing system in gas turbine is analyzed. Through numerical calculation and anlysis, the eigenvalue of gear rotor system, the Logarithmic decrement and the critical speed are obtained. The result shows that the working speed of this gear rotor bearing system is far away from the critical speed, therefore the system is stable and safe. 相似文献
8.
A 28-code gear classification and coding system based on the similarity principle of the Group Technology is set up and key technical characteristics of gear products are obtained. Then the geometrically and technically similar part families are clustered through analyzing the results of gear classification and coding, which lead to the formation of gear product standards. Through combining the core features of gear products with rolling bearing identification code sequence,a 11-product-identification-code system is designed and implemented in one special gear manufacturer enterprise.By employing Visual Basic6.0 and SQL Server2000,a Computer Aided Gear Classification and Coding System oriented to Client/Server was developed and exemplified by one specific case. Application results show that the system effectively groups gear products and efficiently categorize the technical characteristics of those having the same classification code into narrower classes,which propell the standardization of gear design and its production.The situation in which various gears are produced in small batches respectively will be improved by large batch production and finally the professional model of mass-customization production will be realized. 相似文献
9.
Considering that the transmission system of wind turbine works in complex and changing load environment caused by stochastic wind speed,this paper uses sparse least squares support vector machine(SL-SVM) to simulate wind speed of true wind field,and obtains time-varying wind load caused by stochastic wind speed. The lumped-parameter method is used to develop a dynamic model of planetary gear transmission system of wind turbine coupled with bearing. The model includes the varying wind load,time-vary mesh stiffness of gear pair and time-vary stiffness of rolling element bearing. The numerical method is used to simulate the dynamic performance of planetary gear system of Multibrid Technology Wind Turbine with 1.5 MW rated power. The vibration displacement responses of the transmission system are obtained as well as dynamic meshing force each pair of gear and nonlinear bearing forces. The research can provide a foundation for optimizing dynamic performance and reliable design of gear transmission system of wind generator. 相似文献
10.
建立增速齿轮箱动力学分析有限元模型,利用Lanczos法求得齿轮系统的振动模态;以齿轮副时变啮合刚度激励、齿面综合误差激励和轮齿啮合冲击激励为内部作用激励,采用直接积分法求得箱体表面节点的动态响应。选取箱体上12个主要结构参数作为动力学性能优化的设计变量,齿轮箱体积为状态变量,以齿轮箱表面振动加速度的均方根值最小为动力学性能优化的目标函数,利用零阶与一阶优化算法求得最优设计变量。结果表明:优化前后箱体均不产生共振,且满足静力学条件;优化后目标函数减小37.5%,箱体各计算点的振动响应均有较大幅度的减小,最大减小量为54%。 相似文献
11.
This paper introduces phenomenon of electric erosion of gear and the research condition and evolution of it; puts forward a point of view that a system of electric erosion of gear is a especial tribology system which is in relation to many subjects and in which many phenomena exist and coupling each other , moreover , it is very difficult and complex to study electric erosion of gear by experiment ; have made statistical datas about typical example of electric erosion of gear inland ,at this base ,summarizes characters of electric erosion of gear and the study means of it. 相似文献
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13.
Higher-order elliptical bevel gear is a typical form of the noncircular bevel gear transmission.Space spherical coordinate system of the bevel gear meshing is set up based on the meshing theory of space transmission.The varying relationship among the pitch curve,tooth profile and mesh lines are analyzed,and the equation of the gear tooth surface is developed with matrix method based on space coordinate transformation.The basic parameters of the noncircular bevel gear such as transmission ratio,modulus and the number of teeth are designed,and detailed analysis of the influence of the eccentricity on the relevant parameters is carried out as well.By using discrete numerical method and three-dimensional software,the mathematical model of the tooth profile and virtual physical model of the noncircular bevel gear are established,and then simulation on its motion and interference checking are performed.Finally,the approach for design,calculation and generation of the tooth profile is obtained and its correction has been verified by experiment. 相似文献
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15.
Mechanical analysis for the discrete teeth harmonic drive gear pair is carried out. The force on discrete teeth is calculated based on the deformation coordination equation,and the contact stress of meshing pair is obtained by Hertz equation. According to transmission periodicity of the discrete gear harmonic wave and the input angle values of continuous sampling wave generator,the distribution of discrete teeth harmonic drive meshing force and contract stress in rigid tooth profile,tooth wave generator and discrete teeth is obtained. By studying the top cutting phenomena in rigid tooth profiles,the change trend of meshing force and contact stress on the contact surface is found,and positions for high meshing force and high contact stress in transmission are also found,in order to provide reference for further intensity and structure optimization design. 相似文献
16.
LIU Zhongming 《保鲜与加工》2015,(1):133-139
Based on pitting strength, some approaches to enhance power density of gearboxes for wind turbines are discussed. The calculation load is greatly reduced by power division. Allowable stress numbers are effectively increased by improving property of quality materials, precision heat treatment or shot peening. Load capacities can be also obviously enhanced by improving the tooth shape of morphology optimization of tooth root, tooth correction or superfinishing of tooth surface. The center distance is effectively decreased by minishing minimum allowable safety factor or enlarging face width. The power density of gearbox can be further improved by means of structure optimization of planet carrier or uniform load of planetary gear transmission. 相似文献
17.
This paper develops a generalized 3-dimensional 14-DOF dynamic model for hypoid gear which considers the time-varying friction coefficient and lubrication situation. We propose a mixed elastohydrodynamic lubrication(EHL) friction model of hypoid gear tooth contact to reflect the realistic lubricant situation in gear transmission system consisted of full film contact and asperity contact. Under the mixed lubrication condition, the effects of time-varying friction coefficient on gear dynamic is analyzed. The load sharing coefficient is used to calculate the instantaneous friction coefficient at each contact point along the contact path. Friction coefficient model based on mixed elastohydrodynamic lubrication(Mixed EHL) is incorporated into the dynamic model to predict the dynamic mesh force and transmission error with constant and time-varying friction coefficient. The simulation results under a wide range of speed and load show that the time-varying friction coefficient has a marginal effect on the dynamic response. 相似文献
18.
The mesh stiffness of gear tooth is simulated by spring elements, the connected bolt between various housings are simplified as bar elements, and the sliding bearing and rolling bearing are simplified as spring dumping elements. Based on them, the gear-shaft-bearing-housing coupled finite element model and boundary element model of GWC6066 marine gearbox are established. Finally, the dynamic response under internal dynamic excitation is analyzed and the vibration severity, structural-borne noise and air-borne noise of the gear system are forecasted. Through the experimental modal analysis of gear system, and the test of vibration response and air pressure, the natural frequencies, vibration severity, structural-borne noise and air-borne noise are obtained. Compared with numerical results, two results show good agreement. 相似文献
19.
Xiong Tingchao He Yusheng Zhou Hulin 《保鲜与加工》1993,(3):134-139
The basic theory of multi-rigid body system kinematics is introduced, the idea of train component method which relates to kinematics analysis is presented. Using the above theory and method,this paper makes kinematics analysis for the four-axle steering system of LT1080 autocrane. 相似文献
20.
A multi-body simulation approximate model of a vehicle using ADAMS software is established, and a frontrear suspension system, a steering system, the tires and all connectors are studied. Vehicle handling stability under different tests is simulated. The result is credible and valid, the parameter of vehicle model is amended expediently. This simulation can help design products and reduce a development cycle. 相似文献