• Tribology and Lubricants
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• v.30 no.2
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• pp.86-91
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• 2014

This paper presents a design procedure for a face gear and pinion used in a handpiece with a $160^{\circ}\acute{y}$ contra angle and 1:2 gear ratio. Based on the geometric theory of gearing, the tooth profile of the face gear and pinion is developed. To analyze the contact pressure, the gear profile should be determined before calculating the stress between the two gears. The concept of calculating the face gear profile is that it can be generated by the coordinate transformation of the shaper profiles, which have involute curves, using a simulation method from the gear manufacturing process.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.283-289
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• 2018

Agricultural gear reducers are used in a variety of agricultural machinery designs such as in agricultural tractors and transport cars, and even greenhouses. For greenhouses, a gear reducer is used to control windows on the side and the roof. Gear reducers for agricultural applications are designed using the empirical method because of the lack of a standard for experimentation. Simulation is necessary for the optimal design of an agricultural gear reducer. There are many advantages to this optimization such as low-cost maintenance, reduced size, and weight. In this study, bending and contact safety factor simulation for the gear reducer of a greenhouse was conducted by decreasing the face widths of helical gear shaft 2 and shaft 3 from 30.8 and 30 mm, respectively, at an interval of 4 mm. The bending and contact safety factors were calculated using AGMA standard. Simulation results showed that bending and contact safety factors decreased rapidly when the face width of the helical gear on shaft 2 was 30 mm and the face width of helical gear on shaft 3 decreased from 30.8 mm to 26.8 mm, suggesting that it would be safe to reduce the face width of the helical gear on shaft 3 to 26.8 mm. The reduction of the face width also reduced the weight of the agricultural gear. This study suggests that the agricultural gear reducer safety factor decreases as the face width decreases.

• Computers and Concrete
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• v.31 no.2
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• pp.163-171
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• 2023

Face gear transmission is widely used in aerospace shunt-confluence transmission system. Tooth wear is one of the main factors affecting its bearing transmission performance. Furthermore, the installation errors of face gear are inevitable. In order to study the wear mechanism of face gear tooth surface with installation errors, based on tooth contact analysis numerical method and Archard wear theory, the UMESHMOTION subroutine in ABAQUS is developed.Combining with Arbitrary Lagrangian-Eulerian adaptive mesh technology, the finite element mesh wear model of abraded face gear pair is established.The preprocessing conditions are set to generate the inp files.Then,the inp files for each corner are imported and batch processed in ABAQUS.The loading tooth contact problem at each rotation angle is solved and the load distribution coefficient among gear tooth, tooth root bending stress, tooth surface contact stress and loaded transmission error are obtained. Results show that the tooth root wear is the most serious and the wear at the pitch cone is close to 0.The wear law of tooth surface along tooth width direction is convex parabola and the wear law along tooth height direction is concave parabola.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.4
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• pp.45-50
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• 2007

In this paper, the FEM(Finite Element Method) has been applied to understand the geometrical characteristics and to analyze the stress of a helical gear. The helical gear is simulated and analyzed by adding many thin spur gear with helix angles and twist angles. Helical gears with different helix angle and face width have been studied. The results show that the root fillet stress is increased proportionally to helix angle and face width. Namely, as the face width increases, root fillet stress decreases, and as helix angle gets bigger, root fillet stress increases.

• Journal of the Korean Society of Safety
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• v.18 no.4
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• pp.44-50
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• 2003

Design method for involute bevel gears is developed. The developed gear design system can design the optimized gear that minimize the number of pinion teeth with face tooth. Method of optimization is MS(matrix search) which is developed from this study. Design variables are pressure angle 20., transmitted power, gear volume, gear ratio, allowable contact stress and allowable bending stress. etc. Gears design method developed this study can be applied to the plane, helicopter, printer, machine tools.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.263-269
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• 2002

Design method for Involute bevel gears is developed. The developed gear design system can design the optimized gear that minimize the number of pinion teeth with face tooth. Method of optimization is MS(matrix search) which is developed from this study. Design variables are pressure angle 20, transmitted power, gear volume, gear ratio, allowable contact stress and allowable bending stress, etc. Design method developed this study can bd applide to the plane, machine tools, automobiles.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.650-655
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• 2016

Gears are components of transmission which transmit the power of an engine to a machine and offer numerous speed ratios, a compact structure, and high efficiency of power transmission. Gear train design in the automotive industry uses simulation software. However, PTO (Power Take-Off) gear design for agricultural applications uses the empirical method because of the wide range of load fluctuations in agricultural fields. The PTO is an important part of agricultural tractors which transmits the power to various tractor implements. Therefore, a simulation was essential to the optimal design of the PTO. When the PTO gear is optimally designed, there are many advantages such as low cost, reduced size, and light weight. In this study, we conducted the bending and contact safety factor simulation for the PTO gear of an agricultural tractor. The bending and contact safety factors were calculated on ISO 6336 : 2006 by decreasing the face widths of the PTO pinion and wheel gear from 18 mm at an interval of 1 mm. The safety factor of the PTO gear decreased as the face width decreased. The contact safety factors of the pinion and wheel gear were 1.45 and 1.53, respectively, when the face width was 18 mm. The simulation results showed that the face width of the PTO gear should be greater than 9 mm to maintain the bending and contact safety factors higher than 1. It would be possible to reduce the weight of the PTO gear for different uses and working conditions. This study suggests that the possibility of designing an optimal PTO gear decreases as its face width decreases.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.327-335
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• 2020

The purpose of this study was to analyze the load distribution and contact safety factor for the power take off (PTO) gear of a 71 kW class agricultural tractor. In this study, a simulation model of the PTO gear-train was developed using Romax DESGINER. The face load factor and contact safety factor were calculated using ISO 6336:2006. The simulation time was set at 2,736 hours considering the lifetime of the tractor, and the simulation was performed for each PTO gear stage at the engine rated power conditions. As a result of the simulation, the face load factors for the driving gear at the PTO 1^st, 2^nd and 3^rd stages were 1.644, 1.632, and 1.341, respectively. The contact safety factors for the driving gear at the PTO 1^st, 2^nd and 3^rd stages were 1.185, 1.216, and 1.458, respectively. As the PTO gear stage was increased, the face load factor decreased, and the contact safety factor increased. The load distributions for all the PTO gears were concentrated to the right of the tooth width. This causes stress concentrations and shortens the lifespan of the gears. Therefore, it is necessary to improve the face load factor and the contact safety factor with macro-geometry and micro-geometry.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.661-666
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• 2004

The purpose of this study is to measure the rotational vibration, radial vibration, and axial vibration for the helical gear with the wide face width relative to the whole depth. For this purpose, the experimental apparatus is designed and manufactured. The gear vibration of each direction is measured by the accelerometers attached at the gear body. As a result, meshing frequency and second harmonic component are greatly contributed to the gear vibration. As the rotational speed is increased, meshing frequency component has the more significant peak than the second harmonic one. However, the doubled torque decreases the vibration magnitude on the contrary and changes order of the vibration magnitude in each direction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.12
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• pp.953-960
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• 2020

This paper presents an optimization of gear web design used in a main gear train of an engine reduction gearbox for a rotorcraft. The optimization involves the minimization of a total weight, transmission error, misalignment, and face load distribution factor. In particular, three design variables such as a gear web thickness, location of rim-web connection, and location of shaft-web connection were set as design parameters. In the optimization process, web, rim and shaft of gears were converted from the 3D CAD geometry model to the finite element model, and then provided as input to the gear simulation program, MASTA. Lastly, NSGA-II optimization method was used to find the best combination of design parameters. As a result of the optimization, the total weight, transmission error, misalignment, face load distribution factor were all reduced, and the maximum stress was also shown to be a safe level, confirming that the overall gear performance was improved.