• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.129-135
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• 2011

Dry CVT(Continuously variable transmission) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange of the driving pulley has the centrifugal roller and a ramp plate in the flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The main advantages of the Dry CVT with V-belt, which has been popular in Asia, are a simple mechanism, less maintenance and low cost. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study ball type is proposed instead of roller type of movable flange to resolve claim. Also experiments are carried out for new model to evaluate performances.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.85-90
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• 2013

Dry CVT consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study ball type is proposed instead of roller type of movable flange to resolve the claim. Simulation is carried out for new model to verificate performance, experiments are carried out for new model to evaluate performances.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.823-829
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• 2005

The extent of slack is correlative with the wheelbase of vehicle as well as the distance between the inner faces of flanges. Since the movable clearance of wheel flange is getting reduced in curved track, the vehicle is more difficult to negotiate the track. By this reason, a certain extent of slack is normally designed for curved track to allow the movable clearance corresponding to that of straight track. In case of some foreign railways,. the fixed extent of slack has been classified by the ranges of curve radius. In case of KNR, the slack is calculated by a formula for each case of curve radius and it therefore seems quite precise method. However, since there is a wide range of slack adjustment $(S'=0\~15mm)$ in calculation formula itself, too excessive or too little slack can be calculated. This study is to approach the technical review on slack calculation and to offer the reasonable slack design through the full-scale experiment at sharp curved track without slack.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.2
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• pp.59-64
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• 2003

Continuously Variable Transmission (CVT) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The main advantages of the U with V-belt, which has been Popular in Asia, are a simple mechanism less maintenance and low cost. One of the important factors which have an influence on the performance of the CVT is change of axial distance. Base on an experiment the effects of transfer torque and speed ratio of both driving pulley and driven pulley during the alteration of axial distance were studied.

• Journal of Korean Society of Steel Construction
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• v.23 no.3
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• pp.283-294
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• 2011

The variation of temperature in the steel girder bridge by air temperature is measured. A correlation between the daily temperature range, the maximum and minimum temperatures of the day, and the temperature of the bridge are analyzed. With the statistical data from the Korea Meteorological Administration, the temperature correlations analyzed in this study is able to predict temperature variations between the upper flange and the lower flange which calculates the realistic displacement values of a movable support and an expansion joint in design.

• Journal of Power System Engineering
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• v.10 no.3
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• pp.73-80
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• 2006

The main advantages of the Dry CVT with V-belt, which has been popular in Asia, are a simple mechanism, less maintenance and low cost. The important factors which have an influence on the performance of the CVT are the weight of the centrifugal roller, the change of axial distance and spring force. Based on an experiment, the effects of load torque, speed ratio, and revolution of both the driving pulley and the driven pulley during the alteration of the axial distance, roller weight and spring constant were studied.