• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.05a
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• pp.108-111
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• 2002

It is important to predict forming procedure for minimizing trial-and-error in the application of cold forging of gears. In this study, 3-dimensional simulations of cold forging processes of spur and bevel gear were carried out using finite element method to investigate the characteristics of the processes. From the simulation result it was found that incomplete teeth forming of spur gear was occurred with increase of teeth number in forging by forward extrusion. It can be reduced through division of material flows at the initial forming state using forward/backward combined extrusion.

• 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.

• Tribology and Lubricants
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• v.3 no.2
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• pp.72-80
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• 1987

A planocentric torque driver comprises a stationary internal gear with the teeth of a circular concave profile and an external gear of an epitrochoid curve. The contact mechanism of the teeth is examined and analyzed by means of computer simulation. Analyses of load variation on the tooth and strength of appliance is carried out. And the output device is examined. Finally, the design of a 59:1 reduction ratio torque driver is presented.

• Journal of Power System Engineering
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• v.20 no.1
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• pp.57-62
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• 2016

In this study, design the core part of the driving of the robot. The power of the driving is window motor for automobiles obtained by using a method of directly to the motor shaft of the worm gear type. The decelerator consists of a worm gear to receive power from the motor shaft, Helical gear contact to worm gear, a pinion gear to be connected in line with the helical gear, and an output shaft to be engaged to the pinion gear. Drive system by using the power from the motor shaft based on the deceleration gear designed by the gear ratio set by the gear teeth increases the torque.

• Journal of Korean Society for Quality Management
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• v.30 no.3
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• pp.111-119
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• 2002

Gears are essential elements for mechanical power transmission. Geometric precision is the main factor for characterizing gear grade and qualify. Gear pitch is one of the crucial measurements, which is defined as a distance between two adjacent gear teeth. It is well-known that variability in gear pitches may causes wear-out and vibration noise. Therefore maintaining pitch errors at a low level plays a key role in assuring the gear quality to customers. This paper is concerned with a case study, which presents a computerized system for Inspecting pitch errors in a gear machining process. This system consists of a PC and window-based programs. Although the start and stop is manually accomplished, the process of measuring and analyzing pitch data is automatically conducted in this system. Our purpose lies in reducing inspection cost and time as well as Increasing test reliability. Its operation is briefly illustrated by example. Sometimes a strong autocorrelation is observed from pitch data. We also discuss a process monitoring scheme taking account of autocorrelations.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.25-30
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• 2002

To reduce the vibration of a gear driving system, the modification of gear tooth from the orignal involute gear profile is usually done in gear manufacturers. The quantity of tooth modification has been decided on the basis of the interference between two gear teeth during gear meshing and the elastic deformation due to loading. However, the dynamic characteristics with tooth modification has to be investigated to avoid the instability to the variation of gear meshing stiffness and the nonlinearity due to gear backlash which results in sub- or super-harmonics in its responses. This research shows the dynamic characteristics with various tooth modifications in its type and quantity.

• Journal of Biosystems Engineering
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• v.22 no.4
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• pp.497-502
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• 1997

Automation facilities of greenhouses have been continuously developed. However, the conventional two-stage worm gear reducer reveals some problems, including low transmission efficiency. The worm gear reducer also have some difficulties in manufacturing and short life. Therefore, this study was performed to develop a planetary gear reducer, having a high Sear reduction ratio and high torque transmission efficiency. The planetary gear system consisted of a fixed ring gear and a 2-teeth differential ring gear turning slow, as the planetary pinion orbits fast around the fixed ring gear. The developed gear system can achieve a high speed reduction rate at one stage. The reducing system was employed to the greenhouse ventilation system. The reducer has the transmission efficiency of 70.5%, 2∼3 times longer life time, and twofold roll-up torque at an affordable price, comparing with conventional reducers. This reducer can be also applied to many industrial equipments, such as industrial crane, hoist, elevator and gondola etc.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.9
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• pp.688-693
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• 2003

To reduce the vibration of a gear driving system. the modification of gear tooth from the orignal involute gear profile is usually done in gear manufacturers. The quantity of tooth modification has been decided on the basis of the interference between two gear teeth during gear meshing and the elastic deformation due to loading. However. the dynamic characteristics with tooth modification has to be investigated to avoid the instability to the variation of gear meshing stiffness and the nonlinearity due to gear backlash which results in sub- or super-harmonics in its responses. This research shows the dynamic characteristics with various tooth modifications in its type and quantity.

• Journal of KSNVE
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• v.10 no.1
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• pp.74-81
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• 2000

The vibrational model of a helical gear pair is developed with considering the elastic deformation of the active teeth and the body to be a rigid. The main source of vibration in geared system which has been known to be the gear transmission error is mathematically formulated and used for the analysis of vibrational characteristics of geared system. As an example, a simple geared system containing a helical gearing is considered. The critical speeds are found by the campbell diagram and compared with the experimental results.

• International Journal of Automotive Technology
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• v.8 no.2
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• pp.225-232
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• 2007

A tooth profile modification for loaded gears is used to avoid a tooth impact. Since a tooth profile error causes amplification of the cumbersome whine noise in automotive gear transmissions, an optimal quantity of tooth profile modifications must be obtained for good performance in the vibration sense. In this paper, a tooth profile modification curve considering profile manufacturing errors and elastic deformation of the gear tooth is formulated; in addition, transmission errors of the gear system with modified teeth are verified. The equivalent excitation due to transmission errors is formulated. For experimental evaluation of the transmission error, the transmission error for a simple gear system was measured by two rotational laser vibrometers. Finally, we perform a comparative analysis between the calculated and measured responses to the excitations due to the transmission error to verify the practicability of the application to automotive transmissions.