Tooth contact analysis of helical beveloid gear with parallel axis

The study object of this paper is helical beveloid gears with parallel axis. Based on the gear Mshing Principles and the tooth-surface equations of pinion and gear,the mathematical model of tooth contact is developed under standard installation and installations with center distance error,axis error and multiple error respectively. The MATLAB solver is used to obtain the contact trace and the transmission error under different installing conditions and the comparative analysis is made. The results indicate that this gear drive is sensitive to axis installation errors,it forms the edge contact and cause the periodic transmission error. It can provide the foundation for designs and analysis of this gear transmission.     

The machine setting reverse method of spiral bevel gear

The profile error correction of spiral bevel gears is difficult. To solve this problem, the inspected method of spiral bevel gears tooth surface is studied in 3906 gear measuring center. The grids of tooth surface is measured by measurement software. Taking reference tooth surface as the goal, a method of machine setting reverse using approximation algorithms is proposed, and a mathematical model is build. At last, a reverse example based on grinded spiral gear is given. The result shows that the cutting machine setting of bevel gear tooth surface can be exactly calculated.     

Analysis on tooth root stress and influencing factors of crossed beveloid gears with small shaft angle

In order to accurately calculate the tooth root stress of spatial crossed beveloid gears with small shaft angle, an exact geometry-based numerical computation method is proposed based on the spatial gearing theory and the finite element theory. Using the proposed method, the mathematical tooth surface model and the mesh model of a crossed beveloid gear pair with small shaft angle is created and the tooth root stress distribution is analyzed. Then the influences of the key design parameter which is the clearance coefficient, torque load, offset error, shaft angle error, pinion axial position error and gear axial position error on the tooth root stress are investigated. The results show that the increasing of the clearance coefficient can decrease the maximum tooth root stress. The root stresses distribute smoothly along the tooth width direction at a light torque load level. For heavy torque load level, the root stresses are parabolic in shape. Also, the existence of offset error and shaft angle error can increase the maximum value of the root stress obviously and the positive and negative value of the errors can change the position of the maximum root stress along opposite direction. For the pinion and gear axial position errors, they have less effect on root stress distribution.     

Matching Performance Analysis of the Motorcycle

The vibration is a great obstacle of motorcycle enterprise development. To solve this problem, matching performance technology of the motorcycle is presented in the researches on the general design of the motorcycle. Based on finite element method and vibration theory, matching performance of the motorcycle has been studied, and the international general software MSC. PATRAN/NASTRAN has been used to analyze the best match between the engine and the frame of a type of motorcycle. An effective method has been formed, which can solve the problem of the vibration of the motorcycle essentially, and shorten the development period of motorcycle, reduce the development cost. It has very important theoretical meaning and great value in engineering application for motorcycle enterprise to design products.     

Research on pitch cone design for beveloid gears with crossed axes

Based on the spatial gearing theory, the mathematical model for working pitch cone design of crossed beveloid gears is created. The formulas to determine the transition from point contact to line contact are derived. The direct and in direct methods for pitch cone design of crossed beveloid gears are proposed. The effects of gearing parameters on the angle between the first principle directions are analyzed. The loaded tooth contact analysis is performed using FEM theory. The conclusion indicates that: the angle between the first principle directions is more sensitive to cone angles than to the helix angle. The increase of the angle between the first principle directions can obtain smaller contact area, higher transmission error and lower mesh stiffness. A practical tooth bearing test is conducted to demonstrate the proposed design procedure and the experimental result compared well with the simulation. For the matching design and optimization of beveloid gears, it has both the theoretical and project practical significance.     

Intensity Comparative Analysis Based on Ideas Between Involute Gear and Double Involute Gear

Modeler and simulation modules in Ideas software are used to build the finite element models on involute gear and double involute gear with accurate tooth shape, and with the same design parameters and under the same loads, finite element contact analysis has been done. At last, the contact stress and bending stress on the two types gear transmission at the different meshing positions are solved out, and comparative analysis and study have been done. At the same time, that the ladder-shape tooth on the double involute gear how to influence contact stress and bending stress is emphatically analysed. All above offer the theoretical foundation that bring the double involute gear with ladder-shape tooth into the industry.     

Analysis of Radial Force for Compound Gear Pump with Three Idle Gears

Based on the investigation of engaging points' displacement of gear pump with three idle gears ,the radial components of instantaneous hydraulic pressure and the engaging force of the compound pump are analyzed .The research comes to the conclusions that the instantaneous radial forces acting on center and inner gears can be balanced so long as the center gear has triple times tooth ,and the idle gear of even tooth makes less radial hydraulic pulsation than those of odd ones. [WT5HZ]     

contact stress and steady thermal analysis of herringbone gears in a gas turbine

To obtain the distribution characteristic of contact stress and the bulk temperature on the surface of herringbone gears, parameter modeling of gears was carried out by parametric design language. A numerical simulation was given to calculate the contact stress field and the steady thermal field by combining heat transfer theory, tribology theory, and mesh theory. The distribution of contact stress, the bulk temperature and heat flux also were analyzed. The analysis results show that the distribution of the load along the contact line possesses regularity. The heat flux along the tooth depth direction decreases first and then increases. The effect of thermal conduction of the tooth is stronger than that of convective heat transfer. The conclusion indicates that the finite element emulation method can be used to estimate the transmission performance of herringbone gears.     

Analysis of Vibration Experiment for Pedal-motor

Based on the analysis of experimental model, the vibrating experiment was made for the frame and engine of motorcycle in order to find the resonance frequency of the frame. Then the effect of engine exciting on the body vibration was analyzed, so that the mode frequency avoids the range of engine rotation speed. The experiment results show that the vibration of the saddle in vertical direction and the handlebar are caused by the resonance, while the vibrations of the other two directions of saddle and the pedal are the result of the transmission of engine energy. In order to decrease the transmission of the engine energy to pedals, we can change the stiff welding between the pedals and the frame of the motorcycle into the elastic link. Furthermore, to avoid the resonance of the frame in vertical direction, besides increase the stiffness of the frame, we can reduce the stiffness of the frame under the condition of having sufficient intensity, so that the nature frequency of the frame is reduced below the operating speed of the motorcycle engine.     

Review of research on international gear transmissions

Several international conferences on gears is introduced, furthermore, the statistic analysis is conducted on the international gear research in recent years by taking example of the most influential Germany international gear conference. Some important issues on the design, manufacture, and application of gear transmissions is discussed including how to improve the load capacity, suppress vibration and noise, improve transmission efficiency, save resources, improve the efficiency of manufacture, and avoid the environmental contamination, and so on. Main progresses and research highlights of the international gear researches are also introduced and analyzed.     

Simulation of regulatory driving cycle for motorcycle on the engine test bench

Dynamic performance test methods and experiments of motorcycle engine are investigated. The models of clutch, transmission and brake are simulated by changing the resistance torque imposed by the dynamometer to the engine and with the moment of inertia and road resistance data, the model of a 125 mL motorcycle is established on the dynamic engine test bench. On this basis, the road tests are simulated with models of different inertial mass. Compared with the experiments on the drum tester, the results show that when the inertial mass is set to 1.1 times the datum mass of the motorcycle, the deviations of its maximum speed, sliding distance and acceleration time are no more than 3% and the fuel consumption of 100 km is no more than 5% except the speed of 35 km/h. Through driver operational model, the effect of different gear change models on vehicle acceleration performance is studied. Finally, the regulatory driving cycle for motorcycle is implemented on the dynamic bench and the measurements show that it has high ability to accurately control speed.     

Dynamic optimization design of marine gear transmission system

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.     

Profile Precision of Hypoid Gears Controlled by Coordinate Measurements

The geometrical model of profile error is put forward to describe the tooth surface precision of hypoid gears. The influence of each machine tool setting error on profile error is investigated respectively, and the research of the associativity and compensativity among the machine tool errors are made. The setting errors of machine tool, the optimal modifying parameters and their value are got from the measurement coordinates of hypoid gear real tooth surface, and the adjusted manufacturing shows the geometrical precision of the tooth surface is improved effectively.     

Transmission model of higher-order elliptical bevel gearing and motion simulation for interference checking

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.     

Numerical simulation of the internal dynamic excitation of a spiral bevel gear transmission

A 3-D geometry model and a static/dynamic finite element (FE) model of a spiral bevel gear transmission are established. Using ANSYS software, the mesh stiffness excitation of a tooth pair is calculated via the static contact FE method. Using LS     

Identification Method of Acoustic Information Flow of Gear State

According to the transmission way of information flow of gear noise ,we presentthe method of solid state acoustic detection, Noticeing transmission characteristic of the acoustic information flow, we develop and deduce the time domain seperating method. The experimental resultshows that the method can identify gear failure and also can extract the acoustie information flow ofwhich can correctly reflect,the gear moving characteristic , It is very useful to monitor the gear statecharacteristic.     

风电齿轮箱传动误差分析及振动噪声预估

针对一级行星两级平行轴风电齿轮传动系统,综合考虑齿轮时变啮合刚度、啮合阻尼、传递误差等因素,建立31个自由度的弯扭轴耦合集中参数动力学模型,采用变步长Runge-Kutta法对系统动力学微分方程进行求解,得出齿轮传动系统各级传动误差;借助软件建立风电齿轮箱刚柔耦合动力学模型,并导入传动误差,采用模态叠加法求得齿轮箱轴承支反力,并将其作为声振耦合模型的边界条件,采用声学有限元法对风电齿轮箱进行振动噪声预估,并与试验结果对比分析,两者吻合良好。     

Parameter Design for Machining Quenched Internal Helical Gears by EDM

Aiming at the problem of machining quenched internal helical gears, a method and its equipment are discussed and designed, which is used for machining quenched internal helical gears by EDM. Its characteristic and principle are proposed. The modifying design of the electrode gear and the calculating method of its modification coefficients is presented. Analyzing for the error of the machining equipment is done. The results show that this problem can be solved by EDM, the electrode gear is the modification gear of machined gear and the machining accuracy can be improved by controlling errors.     

Bending Stress Analysis on Backlash Adjustable Worm Transmission

The full name of variable tooth thickness plane worm gear transmission is. Backlash adjustable plane worm gear with variable tooth thickness enveloping worm transmission, which is a new kind of accurate power transmission that is intervenient between traditional motion transmission and power transmission. Tooth surface equations of the variable tooth thickness plane worm gear transmission are deduced based on the theory of engagement. Basing on the result, the authors create a finite analysis model of backlash adjustable variable tooth thickness plane enveloping worm with perfect tooth shape by using I-DEAS software, and then has done finite element analysis of backlash adjustable variable tooth thickness plane enveloping worm transmission. Finally, the author drew a conclusion about distribution of principal stress and load distribution between teeth, which offer some references for strength and performance analysis of worm transmission.     

An Electronic Fuel Injection System Based the Monolithic Processor of MC68HC08

According to the motors working principle, the authors design and complet an electronic fuel injection system based the monolithic processor of MC68HC08. Then the authors complete a matching experiment of single-plunger fourstroke engine CG125 applying this system to the trestle. As the system used, fairly well has been settled the contradiction among the driving force of engine, the economization of fuel consumption and the letting of exhaust gas. After the testing, the power of motorcycle engine has increased about 10%, the oil consumption has decreased about 15 %, and the exhaust gas has decreased about 20%,