Elliptical Gears Research Articles

Investigation and Application of Non-sinusoidal Oscillation Technique of Mold

To improve the slab quality, a kind of non-sinusoidal oscillation technique of mold driven by elliptic gears was developed. The waveform functions of non-sinusoidal oscillation were determined, and the calculation method and curves of technological parameters for non-sinusoidal oscillation were given. At the case of waveform deviation factor α equal to 0. 31 and oscillation amplitude h equal to ±2.7 mm, the relationship between oscillation frequency and casting speed is determined, and the technological parameters for non-sinusoidal oscillation are calculated. The testing results of industrial application indicated that this technique could not only improve the slab surface quality, but also reduce the steel breakout.

Анализ контактных давлений при статическом нагружении зубчатых передач эллиптического и эвольвентного типа

Анализ контактных давлений при статическом нагружении зубчатых передач эллиптического и эвольвентного типа

Research on Mathematical Modeling and Kinematic Simulation of Elliptic Family Gears

Elliptic family gears are commonly used in non-circular gears, which include elliptic gear, high-order gear, elliptic deformed gear and high-order deformed gear, thereinto high-order deformed gear can include the elliptic family gears through adjust its order and deformed coefficient. Because non-circular gear has different tooth profile in different position of pitch curve and there is difference in the left and right tooth profile of the same gear tooth, thus the CAD modeling of non-circular gear is difficult for these characteristics; but the precise model of non-circular gear has important significance to the realization of numerical control machining, kinematic simulation and relevant mechanical analysis. This paper deduce the corresponding pure rolling mathematical model based on the pure rolling contact theory that cylindrical gear and non-circular gear mesh in the end face, and realize the CAD modeling of non-circular straight and helical gears by letting the cylindrical gear and non-circular gear make solid geometry operation, which is suitable for pitch curve with convex and concave. The non-circular gear shaping methods with equal polar and equal arc length are simulated by setting different discrete polar angles, and the transmission ratio curve and the angular acceleration curve of driven gear are get through the kinematic simulation of gear pair, which realize the transmission performance analysis of elliptic family gear pair. The above research results can be applied to the modeling and kinematic performance analysis of other non-circular gears.

Parametric Design and Modal Analysis on Four-Order Elliptical Gear

The characteristics of four-order elliptical gear is analyzed. The parameters of four-order elliptical gear are chosen and calculated. The three-dimensional solid modeling of four-order elliptical gear is achieved. The dynamic model of four-order elliptical gear is established by finite element method and modal analysis of four-order elliptical gear is investigated. The natural frequencies and major modes of the first six orders are clarified. The method and the result facilitate the dynamic design and dynamic response analysis of high-order elliptical gear.

Computer Aided Design and Three-Dimensional Modeling of High-Order Deformed Elliptical Gear

The characteristics of high-order deformed elliptical gear is analyzed. The parameters of high-order deformed elliptical gear are chosen and calculated. The modeling method of high-order deformed elliptical gear is presented. The shape of pitch curve is determined. The position and orientation of gear teeth are clarified. The three-dimensional solid model of high-order deformed elliptical gear is achieved. The method and the result facilitate finite element analysis and numerical control machining simulation of high-order deformed elliptical gear.

오발 유량계에 사용되는 타원형 기어 설계에 관한 연구

Elliptical gear is used as a rotor of oval flowmeter. The elliptical gear can assist water flow-rate measurement by the space of the elliptical shape. Presently, elliptical gears have been processed using hob tool imported from Japan. But if it were not for the technical cooperation with Japan company, the Elliptical gears can't be processed. The purpose of this study is developing a domestic technology for elliptical gears and overcoming the dependence of foreign technical skills. It will bring the import substitution effect. In case of pressure angle , the elliptical gears have an interference of tooth. The increase of pressure angle makes the root of a tooth thick and the top of tooth thin. By results of this study, tooth of elliptical gear was designed and verified through the 2D and 3D simulation.

Educational Model for the Kinematic Study of Non-Circular Gears

The noncircular gears are used more and more in industrial applications. The paper presents an educational test rig for the kinematic study of non-circular gears. Two gears are studied from kinematic theoretically point of view: a gear with identically oval spur gears and another gear with identically elliptical spur gears, and simulation diagrams are presented. As for the testing rig, a gear with identically oval spur gears has been used. The researchers are able to draw with high precision the variation curve of output angle with respect to input angle. By using numerical methods for integration and differentiation other diagrams could be drawn and a comparation with simulation diagrams could be made.

Kinematic Analysis on Series Combined Mechanism of Elliptic Gear and Outer Geneva

With elliptic gear as the leading mechanism of Geneva mechanism, the angular acceleration was reduced to decrease the impact of the entering and quitting of geneva. Various factors affecting the angular acceleration were analyzed, and choices of appropriate parameters for the decrease of angular acceleration was discussed.

Reverse Design of Non-Circular Planetary Gears Train Beating-Up Mechanism

A non-circular planetary gears train beating-up mechanism was proposed, the ideal kinematic curve of beating-up rockshaft was constructed and the reverse model of the pitch curve of non-circular gears was established based on the ideal kinematic curve. When the first-level non-circular gears were set as elliptical gears, the maximum swinging angle of the sley and the influence of the elliptical gears' eccentricity on the concavo-convex characteristic of the second-level non-circular gears were analyzed. Provided with a set of parameters, the pitch curves and tooth profiles of the second-level non-circular gears were determined by reverse method. The result has shown that non-circular planetary gears train beating-up mechanism can meet the requirements of beating-up process.

Parametric Design and Modal Analysis on Three-Order Elliptical Gear

The characteristics of three-order elliptical gear is analyzed. The parameters of three-order elliptical gear are chosen and calculated. The three-dimensional solid modeling of three-order elliptical gear is achieved. The dynamic model of three-order elliptical gear is established by FEM and modal analysis of three-order elliptical gear is investigated. The natural frequency and major modes of the first six orders are clarified. The method and the result facilitate the dynamic design and dynamic response analysis of high-order elliptical gear.

S112043 楕円歯車の振動解析([S112-04]伝動装置の基礎と応用(4))

S112043 楕円歯車の振動解析([S112-04]伝動装置の基礎と応用(4))

Study on High-Order Elliptical Gear Parametric Design, Automatic Modeling and Motion Simulation

In this paper, the high-order elliptical gear design principle and methods were studied based on Solidworks API to accomplish high-order elliptical gear parametrical design, machining simulation and automatic modeling. Elliptical gear pair simulation was carried out for verification. The high-order elliptical gear modeling method proposed was to use gear hob type of envelope processing method with the advantages of being able to process concaved pitch curve of high-order elliptical gear. The idea of this design process can also be extended to other types of non-circular gear design and modeling.

Simulation on the vibration characteristics of elliptical gears

Elliptical gear drive is a typical non-circular gear drive, which can be used to transmit a variable-ratio rotation and power simultaneously. To date, elliptical gears are commonly used in automatic machinery, pumps, flow meters and printing presses. However, the vibration characteristics of elliptical gears have not been clarified yet. Due to the non-uniform rotation, the vibration of elliptical gear demonstrates particular characteristics, which should be paid attention to in practical application. This article presents a simulation method on the vibration characteristics of elliptical gears. The torsional vibration simulation model of elliptical gears is established and the simulation programme is developed. The particular gear mesh characteristics of elliptical gears are determined and both the inertial effects of the driving and driven sides of elliptical gears are taken into account in the simulation programme. By means of the simulation programme, two elliptical gear pairs which are a single elliptical gear pair and a double elliptical gear pair and, for comparison, two circular gear pairs which are of the same gear properties as the two elliptical gear pairs respectively are investigated. The torque variations, the rotation speed variations and the circumferential vibration accelerations of elliptical gears are analysed. Furthermore, the critical rotation speeds of tooth separation of elliptical gear drives are obtained and their relations with the load torques are also unveiled. Meanwhile the experiments of the test gears are carried out. The agreement of the simulative results and experimental results proves the validity of the simulation method on the vibration characteristics of elliptical gears proposed in this article.

Kinematic Analysis and Optimization Design of Elliptical Geared Double-Rocker Mechanism

Kinematic characteristics of double-rocker mechanism is analyzed. Based on variable ratio transmission characteristics of elliptical gear, elliptical geared double-rocker mechanism is presented. Kinematic characteristics of elliptical geared double-rocker mechanism is clarified. Eccentricity is optimized. The elliptical geared double-rocker mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

Investigation on the grinding of elliptical gears with CNC conical wheel gear grinder

The grinding of elliptical gears on a computer numerical control (CNC) gear grinder with conical wheel is studied according to the mesh theory of elliptical gears. Two machining methods form the machine structure and movement, namely a mobile grinding wheel type and a fixed grinding wheel type. Mathematical models of the movement relation for the elliptical gear grinding process are built up. Since the teeth of the elliptical gears are different from each other, their generating length is also different. Based on the analysis of generating and indexing movement, a universal generating length formula of each tooth is proposed. Basic machining parameters of each tooth, for these two types of machines, are computed using a practical example. The dynamic simulation of generating track is given. The research results show that the grinding of elliptical gears with a CNC conical wheel gear grinder is feasible.

Kinematic Characteristics and Optimization Analysis of Elliptical Geared Hoeken Mechanism

Kinematic characteristics of Hoeken mechanism is analyzed. Variable ratio transmission characteristics of elliptical gear is obtained. Elliptical geared Hoeken mechanism is presented. Kinematic characteristics of elliptical geared Hoeken mechanism is clarified. Eccentricity is optimized. The elliptical geared Hoeken mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

Graphic Simulation of Hobbing Process for Higher-Order Elliptic Gear

To solve higher-order elliptic gear manufacturing problems, this paper builds the model of hobbing process based on higher-order elliptic gear equation, and researches the graphic simulation technology of hobbing process by using tools (inclined) rack. Four higher-order elliptic spur gears and helical gears with different parameters are simulated by Matlab, to verify the processing model built and the condition of hobbing process can be applied. This work provided the theory foundation for the manufacturing modular of higher-order elliptic gear in CNC System and the reference for its manufacture.

Research on Hobbing Process Principles and Linkage Models for Higher-Order Elliptic Gear

To solve higher-order elliptic gear manufacturing problems, this paper researches the pitch curves of higher-order elliptic gear and its transmission features, and creates the judgment method whether hobbing process can be applied. The four-axle three-linkage hobbing model for spur gear and the four-axle four-linkage hobbing model for helical gear are built by using tools (inclined) rack based on four-axle linkage strategy. This work provided the theory foundation for the manufacturing modular of higher-order elliptic gear in CNC System.

1204 楕円歯車の不等速回転による振動の解析(歯車の動力損失・振動・伝達誤差,一般講演)

In this study, we investigated two elliptical gears which were a single elliptical gear and a double elliptical gear to analyze the vibration of elliptical gears. The tooth root stress, the torque, the rotation speed and the circumferential vibration acceleration of the two elliptical gears and, for comparison, two circular gears with the same gear specifications as the two elliptical gears respectively were measured by the running test. The dynamic load factor and input torque variation of the four test gears were obtained from measured tooth root stress and input torque respectively. Furthermore, the instantaneous output powers of the motor driving elliptical gears were calculated to clarify the reason of the overload of the motor when driving elliptical gears.

Analysis of the Dynamic Characteristics of Elliptical Gears

Analysis of the Dynamic Characteristics of Elliptical Gears