• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.199-200
• /
• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.545-546
• /
• 2007

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.11
• /
• pp.73-82
• /
• 2008

A dynamic model of reducer for generating facility of electric pourer having bevel gear pair and planetary gear train is developed by lumped method. The model accounts for the shaft and bearing flexibilities, gyroscopic effects and the force couplings among the transverse and torsion motions due to gearing. Vibration/noise analysis as well as strength of bevel gear pair and planetary gear train are considered. Exciting forces of high reducer for generating facility of electric power areconsidered as the mass unbalance of the rotors, misalignment and a function of gear transmission error. A Campbell diagram, in which the excitation sources caused by the mass unbalance of the rotors, misalignment and the transmitted errors of the gearing are considered, shows that, at the operating speed, there are not critical speed.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.10
• /
• pp.36-43
• /
• 2020

A marine turning gear is the main auxiliary machine that enables the disassembly of and maintenance on the main engines. In this study, a marine turning gear based on a helical planetary reducer was developed through analysis of a marine turning gear based on a spur planetary reducer. Nonlinear numerical analysis was performed to determine the ideal contact ratio between the sun gear and the idle gear. Based on this, the surface durability, tooth bending strength, and contact ratio were calculated. In addition, the helix direction was selected to utilize the existing bearings. Gears were manufactured based on the helical gear design values, and the turning gear was evaluated using the FTA standards of MAN Co. Ltd. As a result, a lifetime of 3,000 to 5,000 hours was verified, the maximum torque measured was 105kNm, and the efficiency was measured to be 87.4%.

• Journal of Drive and Control
• /
• v.19 no.4
• /
• pp.1-9
• /
• 2022

The structure and operating principle of the 2-speed shift reducer were explained, the allowable bending stress value of the material was compared with the analysis result through FM structural analysis program, and the average stress distribution value of von Mises was performed on the gear root atmosphere. The structural safety of the 2-speed planetary gear reducer was verified through FM structural analysis. The natural frequency was calculated by applying the specifications of the planetary gears of the 2-speed gearbox, and the critical speed of resonance was calculated by calculating the natural frequency and the transmission error of the engaged gear pair. As a result of analyzing the critical speed, since it is formed higher than the actual operating speed range, it is considered safe because there is no resonance problem due to the suggested specifications of the planetary gears of the 2-speed shift reduction.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.6
• /
• pp.195-200
• /
• 2012

In this study, parameters and requirements of an 120kW class monorail planetary gearbox was analysed and the adaptive planetary gearbox design was selected. The specification of the sun gear, planetary gear and carrier was set and the profile & lead was optimized. The mechanical efficiency of the optimized one and the original one was observed. Dynamo-tester system was used to observe the mechanical efficiency of the planetary gearbox. A dynamo unit was connected with the planetary gearbox which straightened through the motor by a coupling. The standard tooth shape planetary gearbox and modified tooth shape planetary gearbox were used as test pieces and the rotation speed was set from 600 to 6000rpm with 600rpm, 2.5min one step. In order to check the mechanical efficiency of the planetary gearbox, the tests were done as follows. 1) The power loss between driving motor and dynamo tester. 2) Temperature variation by different rotation speeds. 3) Noise variation by different rotation speeds.

• Journal of Power System Engineering
• /
• v.18 no.6
• /
• pp.34-39
• /
• 2014

In this study, the structural analysis and the modal analysis are conducted to investigate the stress level, the deformation characteristics and the natural modes of the casing of a planetary gear reducer for a 800kW grade pulverizer mill. The casing is subjected to the load, 2800 kN, from the lump coals in the pulverizing process. Because of the symmetry, the half portion of the reducer casing is modeled for the stress analysis. But the full model is used to find out the eigenvalues and natural modes for the modal analysis. The contact conditions are applied between the thrust pad bearing and the adjacent contacting parts. The results shows that the casing structure has the sufficient strength and stiffness to support the load under consideration. ANSYS version 15 is employed to perform the numerical study.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2001.06a
• /
• pp.360-366
• /
• 2001

This paper show the designing, manufacturing and performance test procedure of a high speed, fixed ratio planetary roller type traction drive as a speed reducer. The arrangement and size design for sun roller, planetary rollers and ring roller are carried out and a proper pre-load mechanism are adopted. To improve transmitting power capacity and endurance limit, nitro-carburized bearing steel and a synthetic traction oil are used. The manufactured and assembled traction drive operated successfully under unloaded conditions. Further tests for various load and speed conditions are executing now to improve the performance of the traction drive.

• Journal of Drive and Control
• /
• v.17 no.1
• /
• pp.1-12
• /
• 2020

This study was to develop a simulation model of a compound planetary gear reducer for the final driving shaft using a gear analysis software (KISSsoft, Version 2017, KISSsoft AG, Switzerland). The aim of this study is to analyze transmission error and the tooth load distribution through micro-geometry using the simulation model. The tip and root relief were modified with Micro-geometry in the profile direction, and crowning was modified with Micro-geometry in the lead direction. The transmission error was analyzed using the PPTE (Peak to Peak Transmission Error) value, and the tooth load distribution was analyzed for the concentrated stress on the tooth surface. As a result of modifying tip and relief in the profile direction, the transmission error was reduced up to 40.7%. In the case of modifying crowning in the lead direction, the tooth load was more evenly distributed than before and decreased the stress on the tooth surface. After modifying the profile direction for the 1st and 2nd planetary gear train, the bending and contact safety factors were increased by 31.7% and 17%, and 18.3% and 12.5% respectively. Moreover, the bending and safety factors after modifying lead direction were increased by 59.5% and 32.7%, respectively for the 1st planetary gear train, and 59.6% and 43.6%, respectively for the 2nd planetary gear train. In future studies, the optimal design of a compound planetary gear reducer for the final driving shaft is needed considering both the transmission error and tooth load distribution.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.23 no.3
• /
• pp.234-239
• /
• 2013

There are many types of speed reducer for industrial uses. However the cycloid speed reducer is widely used in manipulators based on excellent performance of low backlash, high reduction ratio and compact size. It is essential to use precision speed reducer for accuracy of position controls on robot systems and electric vehicles. The cycloid speed reducer has a eccentric rotating motion and offset to avoid some problem of assembly, so it has a disadvantage for vibration. In this paper, a multi-body dynamic model is developed for a cycloid speed reducer and the dynamic behaviors of the reducer are investigated. The cycloid speed reducer consists of cycloidal plate gears, housing gear, input shaft, output pin and shaft, and eccentric bearings. Using a CAD program, each component of cycloid reducer is modeled based on the offset and eccentric. Multi-body simulations using Recurdyn and test using a rig tester are performed. As a result, the pin reaction force and the amplitude of housing displacement are increased by the larger offset and smaller eccentric value of cycloid reducer.