• Journal of the Korea Convergence Society
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• v.2 no.2
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• pp.27-34
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• 2011

This study is making a product for the development of one process worm wheel of making a shape for gear for worm wheel without hobbing manufacturing process. Because of removing a hobbing process, plastic worm wheel for increased productivity and equivalent quality is produced in the result. As the result, this product is selling to Hyundai Mobis, Mando, TRW, KOYO/NSK/Showa(Japan), Delphai(America). The core technology and different strategy are as follows. The technology protection for molding of worm whee is currently patent process "Molding process of helical gear(No. 10-2008-0105908). Further patent procedure for "molding system for positioning decision of inserting boss is currently prepared. As gear molding procedure in hobbing machine without gear machining procedure, most of all, core development technology which is making a gear tooth is main topic. So that, in case of currently developed worm wheel, because core and mold base are not developed in the first procedure, gear is machining in hobbing M/C as the second procedure. In the later, patent for mold base structure will be prepared in this study results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.327-332
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• 2008

New RF matcher module has been proposed in this paper for improvement of RF matcher in plasma etcher system using in semiconductor and display panel manufacturing process. New designed warm gear was used instead of bevel gear in new driving module, and control system was re-arranged with one-chip micro-process technique. The matching performance of new match module was improved in various process condition with reduction of backlash and matching time, and flexible motion of motor compared commercial match module. However this new type RF match module will improve the productivity in etching process of the mass production line.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.99-104
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• 2012

This paper analyzes the pitting's cause of elevator's worm gear type traction machine. To find a cause of pitting problem, we analyzed vibration, a proper design allowance and lubrication. We brought a conclusion that the cause of pitting is not a simple vibration problem, such as misalignment of worm reducer and rail, but mostly related to a designed allowance. In this case, the allowance is tight. In general, the allowance of traction machine and lubrication is varied by manufacturers. When the allowance is tight, a proper lubrication can diminish the pitting problem.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1327-1334
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• 2012

This study shows the conformance-based design results of a fourth-order dynamic actuator showing a performance variation caused by variation in the components as well as aero-induced disturbances. The actuator comprises a BLDC motor, spur gear and worm gear assembly, and canard. The actuator performance was evaluated by using time-variant angle information of the canard. Based on the response surface models, critical system variables were screened using F-tests, and then, the performance was approximated as a function of the variables because it is difficult to determine the performance of a high-order dynamic system as a function of system variables through analytical approaches. In this study, the conformance of uncertain performance to the specification was defined as a probability measure. The design variables obtained by optimizing the measure can provide actuator performance conforming to the specifications considered, even though there is a variation in both the components and the aero-induced disturbances.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.3 s.168
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• pp.162-169
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• 2005

The functional external fixator system fur bone deformity near joints in legs using the worm gear was developed for curing the difference angles in fracture bone and the lengthening bar for curing the difference length in fracture bone. Both experiments and FE analysis were performed to compare the elastic stiffness in several loading modes and to improve the functional external fixator system for the bone deformity. The FE model using the compressive and bending FE analysis was applied to the FE analysis due to the angle differences. The results show that the compressive stiffness value in experiment was 175.43N/mm; the bending stiffness value in experiment was 259.74N/mm; compressive stiffness value in FEM was 188.67N/mm; bending stiffness value in FEA was 285.71N/mm. The errors between experiments and FEA were less than 10%. The maximum stress (157MPa) to the angle of clamp was lower than the yield stress (176.4MPa) of SUS316L. The stiffnesses in both axial compressive and bending of the new fixator are about 2 times higher than other products except EBI (2003).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1248-1251
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• 2004

The functional external fixator system for bone deformity near joints in legs using the worm gear was developed for curing the difference angles in fracture bone and the lengthening bar for curing the difference length in fracture bone. Both experiments and FE analysis were performed to compare the elastic stiffness in several loading modes and to improve the functional external fixator system for bone deformity near joints in legs. The FE model using the compressive and bending FE analysis was applied the FE analysis due to the angle differences. The results show that the compressive stiffness value in experiment was 175.43N/mm, the bending stiffness value in experiment was 259.74N/mm, compressive stiffness value in FEM was 188.67N/mm, bending stiffness value in FEA was 285.71N/mm. The errors between experiments and FEA were less than 10％. The maximum stress (157MPa) to the angle of clamp was lower than the yield stress (176.4MPa) of SUS316L. The stiffnesses in both axial compressive and bending of the new fixator are about 2 times higher than other products except EBI (2003).

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.11
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• pp.1064-1070
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• 2012

This paper analyzes the pitting's cause of elevator's worm gear type traction machine. To find a cause of pitting problem, we analyzed vibration, a proper design allowance and lubrication. We brought a conclusion that the cause of pitting is not a simple vibration problem, such as misalignment of worm reducer and rail, but mostly related to a designed allowance. In this case, the allowance is tight. In general, the allowance of traction machine and lubrication is varied by manufacturers. When the allowance is tight, a proper lubrication can diminish the pitting problem.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2759-2764
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• 2014

Smoke detector is commonly used to reduce fire detection time. However, technical problems regarding its inaccuracy of laser beam-receiving point on the surface of the sensor associated with incoming interference are identified when the laser transmitter and receiver are installed at a distance of about 100m. In this paper, we propose the auto focus alignment algorithm with high precision to adjust tilting angle of lasers caused by environmental interference so that solve existing issues using multi-level worm gear set.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.1
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• pp.49-55
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• 2015

In this study, among in various scenarios of the duration degradation of the fuel cell, countermeasures for the cathode carbon carrier oxidation and the deactivation of catalyst by hydrogen / air interface formation have been studied. so the system was applied to the air cutoff valve. In terms of the component, the cold start performance, electrical stability, the airtight performance were mainly designed and their performance was confirmed. And in terms of the system, the air electrode flow is blocked off, so the oxygen concentration drops when system is powered off, As a result, By reducing unit cell voltage which affect the durability of the fuel cell reached up to 0.8V, the improved durability of the fuel cell was confirmed.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.6
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• pp.582-590
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• 2019

As Korea's low fertility and aging progress, Korea is facing a social change such as an increase of one generation by entering an aging society that has raised 14% of the population. An effective way to prevent a gas fire accident caused by an increase in one generation in an aging society is to install a control valve to forcibly shut off the gas after a set time. In this study, we developed a valve that can be opened and closed by rotating the valve left and right by transmitting power to the worm gear and the helical gear by using a motor by pressing the switch. It is easy to assemble and inspect by developing a dedicated valve that is easy to attach and detach. It was developed to enhance competitiveness by reducing cost by reducing the number of parts and product size. In addition, through endurance test, it was developed to be used for more than 9 years by repeating ON / OFF once every 12 seconds so that it can operate stably for 10,000 times for 34 hours. The instrument and PCB were designed using solid works and Altium Designer tools. Firmware development was developed in IAR Embedded Workbench environment.