• The monthly packaging world
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• s.282
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• pp.93-101
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• 2016

딸기 포장재용으로 새로이 개발된 공중부양형 구조의 용기를 가지고 딸기가 유통 중 발생할 수 있는 짓물림 방지효과가 있는지를 분석하기 위해 일본 후쿠오카 현 쯔꾸시 시에서 도쿄까지 트럭과 항공기에 의한 수송시험을 했다. 일반적으로 사용되는 EPS용기는 수송 중 딸기 간 포장면적이 많아 흠집 발생면적이 컸으며, PET 트레이 위에 딸기를 배열시키는 '보통들이형 용기'는 과일끼리의 접촉부분에서 짓물림 현상이 많이 발생했다. 개발된 '공중부양형 용기'는 과일끼리의 접촉 없이, 유연한 PE필름으로 포장돼 수송 중 발생하는 딸기의 흠집 발생이 가장 적었다. 또한 'EPS 용기' 및 'PET용기'에 25Hz의 정상 진동을 가한 결과, 용기 내부에 발생하는 진동의 주파수 종류에 차이가 있음을 확인할 수 있었다. 'EPS용기'에서는 가진동의 25Hz보다도 큰 주파수의 진동을 많이 확인할 수 있었다

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.12
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• pp.1593-1598
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• 2011

The purpose of this study is to perform parameter selection and develop a method for the condition monitoring of an LCD conveyance robot. To determine the vibration characteristics of the driving part of the robot, the gear mesh frequency (GMF) of the speed-reducing gearbox is calculated and confirmed by frequency analysis. In order to ensure reproducibility of the measured data, an appropriate working pattern is selected and experiments are carried out. For condition monitoring of the robot, a wireless measurement system is constructed and used in parameter selection, with the GMF as the center. A method involving the use of the standard deviation of the measured data and another method involving the use of multiple value of amplitude are proposed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.1-10
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• 1993

A design method of gear tooth profile which can reduce the noise of gear is studied. The tooth profile is generated by combining involute and cycloid tooth curves in which the involute tooth profile is near the pitch point and cycloid tooth profile at the addendum and the dedendum. Considering parameters which have an influence on the reduction of gear noise and building up a design conditions for the noise reduction of gear, the lower-noise combined gear tooth profile is designed. For the check of noise reduction of the combined gear profile, two pairs of combined profile gear, two pairs of involute gear, and a pair of cycloid gear were manufactured by the NC Wire Cutting Machine, and the experiment for measuring of gear noise was carried out on each pair. The noise reduction of the combined profile gear was obtained.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.1
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• pp.41-46
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• 2011

In this paper, we experimentally investigate factors that decrease in noise of a industrial take-out robot at driving state. For this, we analyse change in the noise of the take-out robot with gear machining accuracy and clearance. In order to calculate the noise related to gear machining accuracy that is based upon the Japanese Industrial Standard(JIS), we equally increase motor speed from 0 rpm to 1250 rpm. In addition, to investigate influence of clearance on noise, we evenly change clearance from 0.5 mm to 1.2 mm. These experiments show that clearance is more effective factor than gear machining accuracy to reduce the noise of the take-out robot.

• 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.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.6
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• pp.546-552
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• 2011

In this study, noise sources of a reducer which is combined a spiral bevel gear and a planocentric gear are identified by experimental method and the noise was reduced by the structure modification of the reducer. In order to identify the noise sources, noise and vibration signals were measured by microphone and accelerometer and these signals were analyzed with waterfall plot. In addition, the frequency response functions were obtained to prove the noise and vibration sources. It was found that the resonance was generated by the gear mesh frequencies and natural frequency of the reducer. The noise of the reducer could be reduced by structure modification.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.51-56
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• 2011

In this study, noise sources of a reducer which is combined a spiral bevel gear and a planocentric gear are identified by experimental method and the noise was reduced by the structure modification of the reducer. In order to identify the noise sources, noise and vibration signals were measured by microphone and accelerometer and these signals were analyzed with waterfall plot. In addition, the frequency response functions were obtained to prove the noise and vibration sources. It was found that the resonance was generated by the gear mesh frequencies and natural frequency of the reducer. The noise of the reducer could be reduced by structure modification.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.602-603
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• 2014

A gearbox can be regarded as a self-exciting dynamic system, which has a vibration source. Transmission error (TE) is considered to be an main excitation source for gear noise and vibration. The TE excitation is transmitted through the gears, shafts, bearings, and housings. Thus, an experimental approach to each mechanical parts is useful in order to understand and evaluate the dynamic behaviour of a gearbox. This study is focused on the transmission and vibration characteristics of a helical gear system in development stage. In addition, by considering the tolerance factors and resonance characteristics, the vibration response of actual dynamic system is analysed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.1
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• pp.80-86
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• 2008

In this study. the noise sources were identified and the noise and vibration were reduced for an industrial forklift. To identify the noise sourses, noise signals were measured by a microphone on a driver seat and these signals were analyzed with a waterfall plot. For this purpose, the gear mesh frequencies from the gear box of a reducer were not only investigated but noise/vibration sourses of an electric motor were also examined. Furthermore, the frequency response functions were obtained to confirm the vibration and noise sourses. It was found that severe vibration and noise were generated in the casing and the connecting part of the reducer. The severe vibration and noise could be reduced by a structure modification.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.3
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• pp.308-314
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• 2016

This paper proposes design guidances for noise reduction of a bank teller cash recycler(TCR). The operating noise of a TCR is required to be reduced because it bothers bank tellers and customers. The operating noise from a TCR is measured and the most influential driving system is examined. To find the main sources of the noise, the frequency spectra are analyzed by comparing with excitation frequencies of the driving system. From the analysis results, we reveals that the main sources of the noise are gear mesh frequency of a certain gear train and its side band frequencies, which is attributed by vulnerable support condition. Consequently, to reduce the operating noise, the structural modification for the gear train support is suggested and its effectiveness for the noise reduction is confirmed experimentally.