Design of a Noncircular Planetary Gear Mechanism for Hydraulic Motor

Given the design difficulty and poor accuracy of tooth profile of noncircular gear used in noncircular gear hydraulic motor, it is proposed to reduce the design difficulty and improve the design accuracy by using arc-shaped pitch curve instead of noncircular pitch curve with continuously varying curvature. Based on the geometric relationship and transmission relationship of the noncircular planetary gear mechanism, a nonlinear programming model is constructed for the circular arc-shaped pitch curve. By solving the nonlinear programming model, a noncircular planetary gear mechanism with a modulus of m = 1.5 is designed. The noncircular gear mechanism with the arc-shaped pitch curve was machined and installed in a hydraulic motor, and an efficiency comparison experiment was conducted with a high-order elliptical noncircular gear mechanism with a continuously varying curvature. The experiment shows that the efficiency of the two noncircular gear mechanisms is basically the same, and the best speed range is 100–400 rpm. The noncircular planetary gear mechanism with an arc-shaped pitch curve designed in this paper has reasonable structure, correct transmission relationship, and simple design method, which shows that the design method proposed in this paper has a good engineering application value.

Development of a mathematical model of dynamic characteristics of a drive with a planetary mechanism

The article is devoted to the development of a mathematical model of dynamic characteristics of a drive with a planetary gear mechanism. The subject of research is a drive with a planetary gear mechanism. The following issues were considered in the article: the synthesis of a planetary gear mechanism; the development of a mathematical model that describes the dynamic characteristics of the system; the determination of the dynamic characteristics of a drive with a planetary gear mechanism. Research is based on the method of determining the number of gear teeth; the method of determining the kinetic energy of the James gearbox; the method of determining the dynamic characteristics of an electric motor. The possible number of satellites is given in the article; the pitch radii of the wheels for a given modulus are defined; the moment of inertia of the mechanism reduced to the movable central wheel is determined; a mathematical model of the motion of a drive with a planetary gear mechanism is developed. Equations of motion of a drive with a planetary gear mechanism were obtained. Assuming, in a particular case, all the links of the drive with the planetary gear mechanism as rigid links, a mathematical model was developed for this system, considering the dynamic characteristics of an electric motor. A mathematical model was developed that describes the dynamic characteristics of the system. Analytical solutions for the developed mathematical model are given.

Analysis of Planetary Gear of Toyota Rush AT 2012

Gear is one of the most important part of power transmission system in a vehicle, and as the time goes by there possibly some failure happened on the gears. However, there is no information provided by car manufacturer regarding the life and the material of the gears. This report presents the analysis of the planetary gear used in Toyota Rush AT year made of 2012. The objectives of the research are: to study the planetary gear mechanism and how it works; to analyze the force and stress acting on the gears; and to select a suitable gear material that can withstand against the loads that happen on the gear. The research methodology is started with finding the gear dimension and gear ratio. The force acting on gear is calculated based on the torque and rotation speed provided in car specification. Then the selection material is carried out based on the amount of stress applied on the gear teeth that were calculated using AGMA standard formulation. Finally, the fatigue life prediction of the gears is calculated based on the previous stress acting on the gears. The calculation result suggested AISI 1050 steel as the selected gear material that can carry the bending stress of 476 MPa and categorized as low to high fatigue cycle.