• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.3
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• pp.45-50
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• 2002

This study is an investigation far the Am optimum design using FEA. We write out program which express ADS perfectly and reduce the required time far correcting of model to the minion in solution md manufacture result. We complete algorithm which can plan optimum forming of model by feedback error information in CAE. Then we contract model by feedbback date obtaining in solution process, repeat course following stress solution again iud do modeling rachet wheel for optimum forming. That is our aim. In cachet wheel, greatest equivalence strss originates in key groove comer and KS standard is proved the design far security.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.9
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• pp.1882-1887
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• 2002

This study is to develop a automatic design program of mechanical elements as the integrated system which can create automatically 3-dimensional solid and surface model using visualLISP. By the applying developed system to CAE system, the following objects are realized. At first, constructing the library of automatic design program for unexperienced design engineer, the 3-dimensional modeling of mechanical elements can be obtained easily. at second, the 3-dimensional model for ratchet wheel design is created by finete element model of CAE system and the optimal design condition of key way.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.5 s.182
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• pp.155-161
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• 2006

This paper introduces a new type of mechanical tape feeder for chip mounter. The mechanical feeder is composed of a pneumatic linear actuator and a linear feeding module with the application of a cam-slider. As semiconductor chips are getting smaller, PCB assembly makers require the feeder to position the chip with high accuracy. The linear feeding system improves the positioning accuracy of the chip by getting rid of the index error, which brings into existence on the sprocket rotating feeder. It also can make greatly reduce the dumping rate. The dumping error is caused by the impact occurred as the pawl to interrupt ratchet wheel rotation. The paper discusses its mechanism and mechanical performance. The positioning accuracy and the dynamic characteristic were measured for long time operation and analyzed. As a result, the feeder showed very good performance. However, the feeding system was dynamically unstable due to the cover film eliminator that is required to be modified

• Publications of The Korean Astronomical Society
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• v.36 no.3
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• pp.79-95
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• 2021

This study aims to develop a restoration model of an armillary sphere of Tongcheon-ui (Pan-celestial Armillary Sphere) by referring to the records of Damheonseo (Hong Dae-Yong Anthology) and the artifact of an armillary sphere in the Korean Christian Museum of Soongsil University. Between 1760 and 1762, Hong, Dae-Yong (1731-1783) built Tongcheon-ui, with Na, Kyung-Jeok (1690-1762) designing the basic structure and Ann, Cheo-In (1710-1787) completing the assembly. The model in this study is a spherical body with a diameter of 510 mm. Tongcheon-ui operates the armillary sphere by transmitting the rotational power from the lantern clock. The armillary sphere is constructed in the fashion of a two-layer sphere: the outer one is Yukhab-ui that is fixed; and the inner one, Samsin-ui, is rotated around the polar axis. In the equatorial ring possessed by Samsin-ui, an ecliptic ring and a lunar-path ring are successively fixed and are tilted by 23.5° and 28.5° over the equatorial ring, respectively. A solar miniature attached to a 365-toothed inner gear on the ecliptic ring reproduces the annual motion of the Sun. A lunar miniature installed on a 114-toothed inner gear of the lunar-path ring can also replay the moon's orbital motion and phase change. By the set of 'a ratchet gear, a shaft and a spur gear' installed in the solstice-colure double-ring, the inner gears in the ecliptic ring and lunar-path ring can be rotated in the opposite direction to the rotation of Samsin-ui and then the solar and lunar miniatures can simulate their revolution over the period of a year and a month, respectively. In order to indicate the change of the moon phases, 27 pins were arranged in a uniform circle around the lunar-path ring, and the 29-toothed wheel is fixed under the solar miniature. At the center of the armillary sphere, an earth plate representing a world map is fixed horizontally. Tongcheon-ui is the armillary sphere clock developed by Confucian scholars in the late Joseon Dynasty, and the technical level at which astronomical clocks could be produced at the time is of a high standard.