Type Planetary Gear Research Articles

The Kinematic Design of 2K-2H Planetary Gear Reducers with High Reduction Ratio

The power system equipped in machinery contains power source (motor or engine) and gear reducer to get large output torque. The rotation speed of motor is made higher and higher to obtain high power with the same volume. Hence, the reduction ratio of gear reducer is required to be higher and higher. Planetary gear trains can be used as the gear reducers with high reduction ratio. However, the planetary gear train with high reduction ratio is compound gear system. The purpose of this paper is to propose 2K-2H type planetary gear reducers with high reduction ratio. Based on the concept of train value equation, we propose a new representation to present the kinematic relationship of the members of the train circuit. According to this representation graph, we propose an algorithm for the kinematic design of planetary simple gear trains with high reduction ratio. Some 2K-2H type planetary gear reducers are designed to illustrate the design algorithm.

The Kinematic Design of Three-Speed Automatic Transmission for Electric Motorcycle

Motorcycle is invented so far more than 100 years. Because of having the advantages of light weight, cheap and fast-moving, motorcycle becomes the most popular traffic vehicle. Traditionally, the power systems of motorcycles are internal combustion engines. Recently, due to the reason of energy-saving, and carbon reduction, the engine in motorcycle is substituted by electric motor. Hence, due to the reason of pollution-free, electric motorcycle become more and more popular in city traffic. Planetary gear trains can be used as the transmission systems for electric motorcycles. The purpose of this work is to do the kinematic design of three-speed planetary gear type automatic transmissions for electric motorcycles. First, according to the train value equation of planetary gear train, The reduction ratio equations of planetary gear type automatic transmissions can be derived. Then , based on these reduction ratio equations, the kinematic design of three-speed planetary gear type automatic transmission is accomplished. Based on the proposed methodology, all three-speed planetary gear type automatic transmissions can be synthesized.

On the Meshing Efficiency of 2K-2H Type Planetary Gear Reducer

This paper proposes 2K–2H type planetary gear reducer and analyzes its meshing efficiency. First, according to the concept of train value equation, the kinematic design of 2K–2H type planetary gear reducers is carried out. Three 2K–2H type planetary gear reducers are designed to illustrate the design algorithm. Then, based on the latent power theorem, the meshing efficiency equation of 2K–2H type planetary gear reducer is derived. According to the meshing efficiency equation, the meshing efficiencies of 2K–2H type planetary gear reducers are analyzed. The 2K–2H type planetary gear reducer has the following characteristics. (1) There is a power circulation in 2K–2H type planetary gear reducer. (2) Larger reduction ratio makes less meshing efficiency. (3) For the same reduction ratio, larger value [Formula: see text] will get better meshing efficiency. (4) For 2K–2H type planetary gear reducer, the quality of gears is an important factor. (5) The efficiency of gears manufactured by grinding is only improved by 1.5%; however, meshing efficiency of 2K–2H type planetary gear reducer is improved by 28%~44.8%.

Design and Application of a Planetary Gearbox for Small Wind Turbines

A planetary gear train consists of a sun gear, planet gears, and a ring gear and these gears are arranged as a concentric circle type. The gearbox proposed in this study arranges the planetary gear type as a double planetary gear train in which the output of the primary gear train is used as an input to the secondary planetary gear for accelerating its speed. In this design, a method that directly connects the input and output sections is introduced to obtain a high acceleration ratio and its applicability is verified for applying it to a small wind turbine through designing and fabricating the planetary gearbox.

Design of Third-Order Non-Circular Planetary Gear

The design of the third-order non-circular planetary gear is presented. In order to design the third-order non-circular planetary gear, the pitch of those gears is needed. Firstly theory and composition of the third-order non-circular planetary gear mechanism is introduced. Then according to the two conditions that the pitch should meet, the non-circular pitch formulas of the third-order non-circular planetary gear mechanism is given. Finally an application case of the center distance 3-4 type planetary gear mechanism was calculated by using the designed MATLAB program and created high-order elliptic curve. The design of the third-order non-circular planetary gear is achieved.

Design for NGW Type Planetary Gear Transmission

This article analyzes the NGW type planetary gear transmission mechanism and structure, establishes boundary constraint conditions and mathematics optimization model in view of the smallest volume's project objective. It can realize the NGW type planetary gear transmission optimization design through compiling corresponding computer program, obtain the optimization design parameters. In optimization design's foundation, it applies the CAD technology to establish drawing program, realizes the parametric drawing.

S111045 高減速機構による駆動機構の薄型軽量化研究

A high-rate reduction ratio is obtained by using two kind of laminated planetary gear systems. One layer's planetary gear system is little difference in tooth number or diameter from opposite layer's planetary gear system. The input rotation is from sun gear and the output is not obtained from planet gear's carrier. The reduction revolution is given by the difference between the most out side two rings of internal gear. The first reduction mechanism of laminate type planetary gear is manufactured in one tooth difference In this case the sun gear exist on only one layer and opposite layer have no sun gear because of its each gears' tooth becomes a prim number. Then the planet gear have to be fixed through both layer and delivered on one earner, so named as perfect and imperfect layer lamination. The prime number tooth planet gear delivered on one earner as perfect layer's planet gear position. This manner requires quite fine tooth generating accuracy. This accuracy accomplishment were so difficult as to reach up to 30 % in the efficiency and the noise diminishing. Therefore the second type of perfect and perfect layer were designed, and manufactured in quite small difference in gear diameter. Here state those possibilities of more advanced thin and light weight reduction mechanism by lamination of two kinds of planetary gear system, and circumference multi v-grooved friction wheel planetary layer system, also in addition clutch mechanism for the output layer simultaneous-alternatively exchanging into rotation and counter-rotation on one way sun gear revolution direction.

Research on the Load Sharing Technique and Experimental Validation of NGW Type Planetary Gear Train

In order to solve the problem of load sharing in planetary gear train, the design of planetary gear train was described briefly in this paper. The calculation model of type NGW planetary gear train was established. By analyzing the variety of factors, such as selection of bearing clearance, gear modification, using of flexible structure and the sun gear floating design technology, several ways to improve the load sharing of the planetary gear train techniques were obtained, and they were verified by experiments finally.

Conceptual Design of a 16-Speed Bicycle Drive Hub

This paper presents a design approach for the conceptual design of a novel 16-speed bicycle drive hub. First, a distributed-flow type planetary gear train, which consists of two parallel- connected transmission units and one differential unit, for the power transmission mechanism of a bicycle drive hub is proposed. Based on the kinematic analysis of the presented gear mechanism, a feasible clutching sequence is synthesized to provide 16 forward speeds. Then, the numbers of teeth of all gears are determined according to the desired velocity ratio of each speed. As a result, a schematic diagram of the embodiment of the proposed 16-speed drive hub is presented.

410 部品誤差がスター型遊星歯車装置ねじり共振に与える影響

The influence of the positioning error, the eccentricity or shape error, which is made during the milling process, at the planetary gear center or the internal gear of the star type planetary gear trains to the torsional resonance are discussed using the simulating program. The program was previously confirmed that it can sufficiently simulate the vibration occurrence speed of the rotational shaft and the vibration orbit of the floating sun gear. In the conclusion, the position error of the internal gear center and the planetary gear center make the change of the self-centering position of the floating sun gear and the shape of the movable area of the sun gear. But they are not the cause of the resonance, because the resonance does not occur without the forced torque. The eccentricity of the planetary gear can be the cause of the resonance when the rotation speed of the planetary gear becomes the natural frequency of the rotating shaft. But the eccentricity of the internal gear is not the cause of the resonance. The triangle shape error of the internal gear, which is measured in the experiment, also simulated. And it is made clear that the shape error can be the cause of the resonance. This can be considered that the transmission error can be made by the coincidence of the shape and the number of planetary gears.

Modeling of the process of gear shifting in planetary gear trains of motor vehicles

Gear boxes, i. e. the realization of their functions, especially gear shift, have a big impact on vehicle operation quality through their effects on the performance of vehicles and their comfort. This paper shows a method of modeling the transition process during gear shifting in planetary gear trains. The simulation model is developed with in order to provide virtual research of planetary gear trains, which would positively decrease the number of real prototypes, thus considerably saving time and contributing to the quality improvement of the final product (planetary gear train) and vehicles in general. Introduction Modeling of gear shift processes has been carried out on the planetary gear type Ravigneaux used in planetary gear trains of motor vehicles. The model was developed modularly, so that more simulation models can be added to the whole. At the same time each subsystem is a model for itself and can be used independently from the main model. Simplified engine model Bearing in mind that, for the simulation of the planetary gear which is the subject of this paper, the necessary input parameters are in the form of engine torque Mm, angular velocity and motor ωm moment of inertia of rotating engine components reduced to the input shaft gear, a simplified model of an internal combustion engine has been formed. Model of external load External load resistance is in the form of the torque Mt occurring on the drive wheel of the vehicle. On the other hand, this load is defined by the moment of inertia of rotating elements from the planetary gear to the drive wheel, reduced to the output shaft. Model of friction transmission simulation Transmission power control in planetary gears is achieved through friction components. The output size of this subsystem is the moment of carrying the friction assembly. Simulation model of the planetary gear train The model simulation of the planetary gear type Ravigneaux was formed in accordance with the kinematic scheme of the gear train. The gears are presented as a solid body defined by mass, moment of inertia, position with respect to the system and the center of gravity. Subsystem for monitoring the simulation results Measuring and recording the simulation results are simulated with the simulation tracking subsystem. The simulation results are described through the torque and the angular velocity as a function of time. Analysis of the simulation model Forming a simulation model enables virtual testing of the planetary gear and the analysis of the impact of certain parameters on the behavior of the gear during gear changes. In other words, an opportunity has been created to examine the behavior of the model while simulating different conditions. Conclusion This paper presents the modeling of the gear change process in a planetary gear using computers in the Matlab / Simulink environment. Computer-aided modeling of the gear change process enables the generation of different versions of virtual gear models with relevant data about their characteristics thus helping designers in their decision making in the iterative process of design, i. e. in making appropriate decisions in the early stages of design.

Effects of Roughness and Coating on Frictional Behavior of Planetary Gear Type of Torque-Sensing LSD

Effects of Roughness and Coating on Frictional Behavior of Planetary Gear Type of Torque-Sensing LSD

A study on the bending stress of the hollow sun gear in a planetary gear train

Generally, planetary gear type traveling reduction gear is composed of multiple planetary gear stages and has a hollow sun gear in the last stage planetary gear. In designing reduction gear, it is important to evaluate accurately the bending stress at the tooth root of the sun gear as the sun gear is the weakest component in the reduction gear system. Although bending stress can be calculated easily using gear standard codes such as the American Gear Manufacturers Association (AGMA) and International Organization for Standardization (ISO) 6336 for almost all gears, meticulous calculation is needed for the hollow sun gear because of its low backup ratio (rim thickness divided by tooth height) and comparatively large root fillet radius. In this study, a finite element analysis (FEA) is carried out to investigate the effect of rim thickness and root fillet radius on bending stress at the tooth root of the hollow sun gear. In standard codes, bending stress at the tooth root is calculated linearly with a constant slope for the backup ratio below 1.2. However, the effect of the rim thickness on bending stress is more complex in the planetary gear system. Bending stresses calculated by FEA with various backup ratios and root filler radii are compared with the bending stresses calculated by the standard codes.

Development of Planetary Gear Type Steering System with Power Assist Using Torque Split Control of Traction Motors and It's Application to Aged Drivers

Development of Planetary Gear Type Steering System with Power Assist Using Torque Split Control of Traction Motors and It's Application to Aged Drivers

Analysis of Dynamic Load Sharing Behavior in Planetary Gearing

A calculative model for single stage planetary gear (type 2K-H) is presented with the dynamic way. In consideration of the manufacturing and assembly errors of parts, the vibratory equation of each planetary gear is found by using the theory of equivalent mesh error and equivalent mesh stiffness, and the dynamic analytic model is built. The load sharing behavior of each planetary gear is studied by using the theory of equivalent mesh error and equivalent mesh stiffness, and then the relationship between error and load sharing is analyzed. The calculation results are in good agreement with the known experimental results. The analysis results indicate that the floating sun-gear can improve the load sharing behavior greatly, and the assembly and fixing errors altogether react on the load sharing character. No good effect can be achieved by only decreasing one error. The rotating speed influences the load sharing greatly.

Multi-objective reliability optimization design of tractor's NGW type planetary gear final transmission

Multi-objective reliability optimization design of tractor's NGW type planetary gear final transmission

Sliding mode control with self-tuning law for uncertain nonlinear systems

A robust sliding mode control that follows a self-tuning law for nonlinear systems possessing uncertain parameters is proposed. The adjustable control gain and a bipolar sigmoid function are on-line tuned to force the tracking error to approach zero. Control system stability is ensured using the Lyapunov method. Both simulation and experimental application of a planetary gear type inverted pendulum control system verify the effectiveness of the developed approach.

MICRO-ELECTRIC VEHICLE FOR AGED DRIVERS WITH PLANETARYGEAR TYPE ACTIVE STEERING SYSTEM

A planetary gear type active steering system for μEV which is possible to be adjusted to driver's characteristics is developed. The system has also the torque assist/augmentation system using torque split control of the in-wheel traction motors. The system characteristic is adjusted to the aged drivers and the effects of the system on the drivers are experimentally proved. It is confirmed that the characteristics of the driver change according to the steering characteristics as a result the system can compensate for deteriorated control ability. The torque augmentation control is also proved to be effective on improving on-center handling characteristics of the vehicle.

1104 遊星ギア機構と左右輪駆動力差によるパワーアシストを有するμEV用ステアリングシステムの開発とその応用(高齢運転者に適応した高度運転支援システム,TRANSLOG 2006)

1104 遊星ギア機構と左右輪駆動力差によるパワーアシストを有するμEV用ステアリングシステムの開発とその応用(高齢運転者に適応した高度運転支援システム,TRANSLOG 2006)

Performance Evaluation of Innovative Micro-Traction-Drive-Utilized Angular-Contact Bearing

Traction drive makes oil film between two rollers, and power is transmitted by oil film shearing. It has the following characteristics. (1) Traction drive can be operated at low level of vibration and noise, so they are more suitable at higher speed rotations than gear. (2) Traction drive can change continuously the distance from the contact point of the rotating part to the axis of rotation; it is useful in continuously variable transmission (CVT). Generally-fixed-reduction-ratio-type traction drive is developed for the purpose of use by high-speed rotation taking advantage of the feature of characteristic (1). On the other hand, the authors have developed a micro drive system for transmission; a micro-traction-drive based on the structure of an angular ball bearing is advantageous over geared speed reducers, for small scale equipment requiring high numbers of revolutions. A micro-traction-drive is easily manufactured by modifying angular bearings and tapered roller bearings for which preload inner race and outer race act as thrust force. The driving force is transmitted by the contact of the retainer with the rolling element in the rotating direction. The test of the experimental model of micro-traction-drive using an angular ball bearing of 10mm inner diameter, 30mm outer diameter, and 9mm width was carried out. Power-absorbing-type test equipment was made and the input and output torque, number of revolutions, temperature, noise, and state of lubrication were measured. With the same test equipment, the micro-traction-drive was compared to the equivalent type planetary gear with outer diameter of 32mm on the market. In comparison with commercially available speed reducers, the planetary gear system, the newly developed micro-traction was found to bear superior performance in terms of allowable transmission torque, efficiency, noise, and other characteristics.