Investigation of planet gear instant center of rotation under three-axis driving differential planetary gear train with graphical analysis using high speed camera

Planetary gear trains (PGTs) are widely applied in various machines owing to their advantages, such as compactness, low weight, and high torque capacity. However, they experience the problems of vibration due to the structural and motional complexities caused by planet gears. In a previous study, it was shown that high speed monitoring is effective for evaluating the motion of planet gears under steady conditions and transient conditions including the influence of backrush. However graphical investigation was conducted manually, and improvement in accuracy is required. In this report, an improved method is proposed, which includes lighting conditions and measurement conditions. Throughout these improvement processes, instant center of rotation is calculated automatically with detected coordinates using software. This makes it possible to estimate the transient response of PGTs with planet gear motion.

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A PLANETARY GEAR TRAIN WITH RING-INVOLUTE TOOTH

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2008-0016 ◽

2008 ◽

Vol 32 (2) ◽

pp. 251-266

Author(s):

Shyue-Cheng Yang ◽

Tsang-Lang Liang

Keyword(s):

Planetary Gear ◽

Conjugate Problem ◽

Gear Ratio ◽

Gear Train ◽

Tooth Surface ◽

The Sun ◽

Ring Gear ◽

Planetary Gear Train ◽

Envelope Method ◽

Planet Gear

This paper proposes a planetary gear train with ring-involute tooth profile. Inherent in a planetary gear train is the conjugate problem among the sun, the planet gears and the ring gear. The sun gear and the planet gear can be obtained by applying the envelope method to a one-parameter family of a conical tooth surface. The conical tooth rack cutter was presented in a previous paper [5]. The obtained planet gear then becomes the generating surface. The double envelope method can be used to obtain the envelope to the family of generating surfaces. Subsequently the profile of a ring gear of the planetary gear trains can be easily obtained, and using the generated planet gear and applying the gear theory, the ring gear is generated. To illustrate, the planetary gear train with a gear ratio of 24:10:7 is presented. Using rapid prototyping and manufacturing technology, a sun gear, four planet gears, and a ring gear are designed. The RP primitives provide an actual full-size physical model that can be analyzed and used for further development. Results from these mathematical models are applicable to the design of a planetary gear train.

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Research on Calculation of Unloaded Transmission Error of Planetary Gear Train Caused by Eccentricity

Volume 10: 2017 ASME International Power Transmission and Gearing Conference ◽

10.1115/detc2017-67463 ◽

2017 ◽

Author(s):

Shuaidong Zou ◽

Guangjian Wang ◽

Li Yu

Keyword(s):

Curve Fitting ◽

Planetary Gear ◽

Transmission Error ◽

Gear Train ◽

Computational Formula ◽

Planetary Gear Train ◽

Ratio Error ◽

Load Transmission ◽

Planet Gear ◽

Load Conditions

In this paper, calculation of no-load transmission error (TE) of planetary gear train is studied. The theory computational model of the eccentric planetary gear train with single planet gear (SPG) under no-load conditions is constructed initially for acquiring the formulas of no-load transmission ratio error and unloaded transmission error (UTE) of internal and external gear pairs. Then computational formula of the UTE of planetary gear train with SPG caused by eccentricity is presented. Through simulation TE and the developed formula of UTE, the eccentricities and initial phasing are uncoupled by curve fitting. Simultaneously, formula of UTE of planet gear train with SPG is validated. At the same time, different groups of initial phasing are analyzed to acquire the relatively good initial phasing group. In addition, the UTE of planetary gear train with multiple planet gears (MPG) caused by eccentricity is developed.

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Design of a non circular gear Mechanism with Twice Unequal Amplitude Transmission Ratio

Journal of Mechanisms and Robotics ◽

10.1115/1.4053472 ◽

2022 ◽

pp. 1-13

Author(s):

Jiangang Liu ◽

Zhipeng Tong ◽

Yu Gao-hong ◽

Xiong Zhao ◽

Haili Zhou

Keyword(s):

High Speed ◽

Planetary Gear ◽

Tooth Profile ◽

Gear Transmission ◽

Gear Train ◽

Transmission Ratio ◽

High Speed Camera ◽

Contact Ratio ◽

Ratio Curve ◽

Amplitude Transmission

Abstract This study proposes a new non–circular gear transmission mechanism with an involute–cycloid composite tooth profile to realize the twice unequal amplitude transmission (In a complete rotation cycle of gear transmission, instantaneous transmission ratio has twice fluctuations obvious with unequal amplitude) of non–circular gears. The twice unequal amplitude transmission ratio curve was designed based on Fourier and polynomial functions, the change law of the Fourier coefficient on the instantaneous transmission ratio(In non-circular gear transmission, the transmission ratio changes with time, and the transmission ratio of non-circular gear should be instantaneous transmission ratio) was analyzed, and the pressure angle and contact ratio of the involute–cycloid composite tooth profile was calculated. The involute–cycloid composite tooth profile non–circular gear was machined by WEDM technology, while its meshing experiment was performed using high-speed camera technology. The results demonstrate that the instantaneous transmission ratio curve value obtained via the high-speed camera experiment was consistent with the simulation value of virtual software. Furthermore, the involute–cycloid composite tooth profile was applied in the seedling pickup mechanism of non–circular gear planetary gear train. The possibility of the application of the involute–cycloid composite tooth profile in the seedling pickup mechanism was verified by comparing the consistency of the theoretical and simulated seedling picking trajectory.

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A Novel Algorithm for Enumeration of the Planetary Gear Train Based on Graph Theory

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.199-200.392 ◽

2011 ◽

Vol 199-200 ◽

pp. 392-399 ◽

Cited By ~ 2

Author(s):

Ming Yue Ma ◽

Xiang Yang Xu

Keyword(s):

Graph Theory ◽

Mechanism Design ◽

Planetary Gear ◽

Gear Train ◽

Enumeration Algorithm ◽

Planetary Gear Train ◽

The Core ◽

Planet Gear ◽

Gear Trains ◽

Novel Algorithm

As well known, graph theory is a powerful tool for mechanism design. The enumeration of planet gear trains can be converted the synthesis of graphs while a planetary gear train is converted to a graph. During the enumeration of graphs, the problem of isomorphism should be solved. This paper proposes a novel algorithm used to generate non-isomorphism graphs and thereby omits the part of isomorphism detection. The vertex characteristic is firstly defined in this paper that is the core of the enumeration algorithm. This paper also gives an example of the application for the algorithm.

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