• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.86-86
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• 2004

무단변속기는 속도비를 연속적으로 변화시킬 수 있고, 자동차에 적용할 경우 엔진속도를 차량속도와 독립적으로 제어함으로써 동력성능과 연비성능을 동시에 만족시킬 수 있는 장점을 가지고 있다. 무단변속기는 다양한 종류가 개발되어 사용되고 있으나, 이들 대부분은 자체적으로 중립(geared neutral)을 구현할 수 없거나 효율과 수명 측면에서 기존의 유단변속기(기어 변속기)보다 불리한 단점을 가지고 있다.(중략)

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.2
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• pp.67-75
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• 1997

The noise . vibration characteristics of Hypoid gears which were made from three seperate materials(SCM, TSCM, SNCM) under the identical process were investigated for the sake of durability improvement of differential gear compatible with low level noise gear set. For this study, we developed a rig experimental equipment which can perform close noise.vibration experiment of differential gear. Consequently, we could analyze the noise.vibration characteristics of final reduction gear by materials, and also we observed changes in both metallic structure and hardness according to the materials of pinion gear. In addition to this, the correlation between the vibration of the differential gear and the interior noise of the passenger vehicles was proved by analyzing the results of rig vibration experiment and field noise test.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.04a
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• pp.277-283
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• 1991

일반적으로 건설중장비에 쓰이는 주행용 감속기의 종류에는 차동유성기구(Differential Planetary Drive), 2단유성기구(Two Stage Planetary Drive), 3단유성기구(Three Stage Planetary Dnive)가 있으나 전체적인 감속기의 성능 및 특성에 대해서는 자세히 알려져 있지않아 주행시스템의 국내개발이 미흡한 상황에 있다. 따라서 본 연구에서는 이러한 문제점의 1차적 해결책으로서 주행장치에 채용될 Heavy Duty용 유성기어 감속기를 차동유성기구 한개 모델과 2단유성기구 두개 모델을 시제품으로 제작하여 종류별로 동력전달효율과 감속기 내부 온도상승의 관점에서 그 성능을 비교 분석하여 각각의 특성을 제시하였다.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.3
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• pp.279-284
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• 2009

This study investigates the stress at gear by modelling differential gear and using FEM. When gear is driven under power, high equivalent stress of 1596.2MPa is occurred at the stationary shaft. Maximum equivalent stress of 1596.2MPa is also occurred at the bottom and root of tooth and its fatigue life becomes 12.4 as the shortest cycle. As much as it becomes away from the center of gear, the maximum deformation becomes occurred. As exact power is delivered with the precise design of gear, the loss of power energy can be decreased.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.4
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• pp.170-178
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• 2004

Continuously variable transmission (CVT) mechanisms considered here are input coupled types that combine the functions of a 2K-H II type differential gear and a V-belt type continuously variable unit (CVU). For the 8 different mechanisms, 4 of them are power-circulation modes while the other 4 are power-split modes, various performance analysis (speed ratios, power flows, divisions of power transmission in a differential gear and a CVU, and theoretical efficiencies) are performed to vary design parameters. Experimental studies are executed to validate fundamental relations (speed ratios, power flows, efficiencies, occurrence of geared neutral). Some useful characteristics associated with performance also are discussed in the mechanisms.

• 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.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.99-106
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• 1999

Because many light rail transit systems are mainly operated in the downtown areas of a large cities and the congestion areas, there are many steep gradients and sharp radius sections in that lines. As that reasons above, light rail vehicles are equipped with differential gear units between traction motors and final reduction gear units. In this paper, the configurations and the interferences of 2K-H I type Planetary gear train, which is applicable for light rail vehicles and based on various differential gear units, are studied. The ranges of addendum modification coefficients which would not lead to interferences is analyzed, and optimal addendum modification coefficients among these ranges are presented, which generate the maximum efficiency of planetary gear drives and differential gear unit as pressure angles, speed ratios,

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.6
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• pp.597-604
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• 2000

본 연구에서는 전기자동차에 사용되는 전자식 차동 시스템의 신경망 모델을 제안한다. 차량이 곡선도로를 따라 주행할 경우 내측 바퀴와 외측 바퀴의 회전속도가 서로 달라야 진동이나 뒤틀림 없이 완만한 선회 주행을 할 수 있다. 전기자동차는 그 구조적 특성상 각각의 바퀴가 독립된 구동원을 갖는다. 이 때문에 일반 엔진 차량의 기어식 차동장치를 대신할 전자식 차동장치가 요구된다. 이러한 차동장치는 차량의 구조뿐만 아니라 차량의 주요 파라미터인 조향각 및 속도에 따라서 비선형적인 관계를 가지고 있어서 해석하기가 쉽지 않다. 따라서 이와 같은 비선형적인 관계 모델을 학습 능력을 가진 신경망에 의하여 모델링 함으로써 제어에 적용할 수 있다. 이를 실현하기 위해 제작한 전기자동차로 곡선도로를 주행하여 다양한 곡률과 주행속도에 따른 내측 외측 바퀴의 회전속도 데이터를 획득하고, 데이터의 비선형 특성을 고려한 차동 속도 제어기의 구조를 설계한다. 이 제어기에 적합한 모델은 신경망을 이용하여 실측 데이터를 학습시킴으로써 차동기능을 수행할 수 있는 제어기를 구현한다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.1
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• pp.8-15
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• 2011

ATV(All Terrain Vehicle) has been developed to be used for agricultural fields on unpaved roads but now it is mostly used to transport a short distance and play leisure sports at mountains. Recently, main concerns on the automobile industry is developing not only a car safe, high fuel efficient and friendly related with environment but also two-wheeled vehicles. In order to maintain high fuel efficiency and safety of two-wheeled vehicle, it is essential that ATV should be set up differential gear. But we worried for ATV which had been set up differential gear not to run on unpaved roads. Therefore, it is necessary to develop LSD(Limited Slip Differential) that maintains existing advantages of ATV and ensures ATV to travel safely on roads. Now LSD equipped cars have a complicated structure, so setting up on ATV is unsuitable. Therefore, in this study, we have developed simple, small and well operating LSD.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1060-1068
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• 2002

Compound continuously variable transmission(CVT) mechanisms are proposed, which can offer a backward mode, a geared neutral, an underdrive mode and an overdrive mode. They are composed of a 2K-H I type differential gear unit, a V-belt type continuously variable unit(CVU), a few friction clutches and gears, and not required of a starting device as a torque converter. Compound CVT mechanisms developed here present two distinct operating modes which are a power circulation mode and a power split mode. The transition of two modes takes place at the particular CVU speed ratio. For these CVT mechanisms, performance analysis related to speed ratio, power ratio and efficiency are executed and proven by experimental studies.