• 한국전자통신학회논문지
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• 제8권3호
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• pp.403-408
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• 2013

본 연구는 자동차 브레이크 패드 생산 공정에서 컨베어벨트 실려가는 차종별 패드의 유형을 자동 판별하고 표면의 균열을 검사하는 시스템을 개발한다. 브레이크 패드는 여러 혼합제로 고열, 고압 성형하여 만든다. 패드생성과정에서 패드 표면의 균열 및 손상이 발생한다. 본 연구에서는 불량품을 검출하는데 적합한 시스템 구축하고 응용소프프웨어 개발을 한다. 패드 표면의 균열이나 손상 부위는 인공조명을 비출 때 그림자를 생성하게 되며 이를 컴퓨터 비전 기술을 활용하여 검출한다.

• 한국산학기술학회논문지
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• 제14권7호
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• pp.3158-3163
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• 2013

본 연구에서는 회전속도, 브레이크 압력 제어가 가능한 브레이크 다이나모메타를 제작하여 스퀼 소음 실험을 실시하였다. 브레이크 패드는 각각 $34^{\circ}$, $30^{\circ}$, $26^{\circ}$로 가공하여 패드 각도에 따른 스퀼 발생 조건과 음의 기울기 발생에 따른 스퀼 연관성을 연구 하였다. 각도에 따라 특정한 회전속도와 브레이크 압력에서 스퀼이 발생하였으며, 각도에 상관없이 하모닉 성분을 가지는 특정 주파수 소음을 발견하였다. 햄머링 테스트 및 유한요소해석을 통해서 특정 주파수는 In-plane모드 성격을 갖고 있으며, 패드 각도에 둔감한 모드임을 밝혀냈다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.429-430
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• 2002

In this study, three kinds of brake: discs including two coated brake discs and one steel disc were tested under the same experimental conditions on a reduced scale braking test bench. Plasma spray coating technique was used to coat ceramic powder on the discs. In the test, four commercial sintered brake pads were coupled with discs. Ceramic coated discs have shown good stability in friction coefficient at high speed and high energy braking conditions. However, ceramic coated discs caused more wear loss of pad mass than the steel disc. It was shown that thermal barrier effect in ceramic coated discs adjusted the thermal partition between pad and disc. Steel disc showed fluctuating friction coefficient at high speed but less wear loss of pad mass than ceramic coated discs.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.975-985
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• 2011

Cu-Matrix sintered brake pads and low alloyed heat resistance steel are most applied to basic brake system for high energy moving machine. In this research, we analyzed tribological characteristics for influence of air velocity between disk and pad. At low brake pressure with air flow, friction stability was decreased due to no formation of tribofilm at disk surface. But there are no significant change of friction coefficient at all test conditions. Wear rate of friction materials were decreased with increasing of air flow velocity. In result, air flow velocity influenced friction stability, wear rate of friction materials and disk but not friction coefficient.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.315-321
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• 2004

Dawin Friction Corp. has been advanced sintered brake pad for Korean concept high speed train (so called G7 train) with KRRI, You Jin and Rotem without the assistance of foreign company. In the course of development, the evaluation of our and foreign disk pads was performed by lab scale dynamometer and full scale dynamometer. As the result of dynamo test, it is shown that our developed brake disk is equal or superior to those of foreign companies in many respects, for example, wear resistance, noise, etc. The new brake pad which is developed through 'post G7-project' is equipped with G7 train and is under many tests without any problems at the present moment.

• Tribology and Lubricants
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• 제29권2호
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• pp.98-104
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• 2013

Cu-matrix-sintered brake pads and heat-resistant low-alloy steel are commonly applied to basic brake systems in high-energy moving machines. We analyzed how the tribological characteristics are influenced by the inertial mass. A high inertial mass decreased the friction coefficient by about 15% compared to a low inertial mass under all velocity conditions. The wear rates of the friction materials increased with the inertial mass. Thus, the inertial mass influences the friction coefficient and wear rate of the friction materials and disk but not the friction stability.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.274-280
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• 2006

The study is to analyze dynamo test results for various commercial pads in order to verify the performance of brake disk with CV-NCM cast iron. The developed brake disk will apply to 200 km/h tilting trains that is being developed as one part of project for speed-up on Korean existing railroad. The test program is made out suitably for braking condition and performance of test equipment by referring UIC 541-3. Two kinds of resin pad and one kind of foreign sintered pad suitable for 200 km/h trains are used as various commercial pad for the dynamo test. The data aquisition for the maximum and smallest temperature, hot spot, etc. on disk and pad is performed by using the thermocouples and thermal imaging cameras. From this research, we obtained braking characteristics between CV-NCM cast iron disk and pad of various material and will be utilized usefully as basis data of performance optimization of developing sintered pad.

• 한국자동차공학회논문집
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• 제24권1호
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• pp.1-9
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• 2016

Optimum cross-sectional shape of an automotive disc brake was developed based on FEM thermal analyses and the Taguchi method. Frictional heat flux and convection heat transfer coefficients were first calculated using equations and applied to the disc to calculate accurate temperature distribution and thermal deformations under realistic braking conditions. Maximum stress was generated in an area with highest temperature under pads and near the hat of ventilated disc and vanes. The SN ratio from Taguchi method and MINITAB was applied to obtain the optimum cross-sectional design of a disc brake on the basis of thermal deformations. The optimum cross-section of a disc can reduce thermal deformation by 15.2 % compared to the initial design.

• Tribology and Lubricants
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• 제25권1호
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• pp.49-55
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• 2009

The frictional properties of automotive brake pads with four different ceramic materials such as magnesia, hematite, alumina, and zircon were investigated. A Krauss type friction tester using gray iron disks was used to examine the friction coefficient, intensity of friction force oscillation, and the tribe-surfaces. Results showed that the friction coefficient increased as the hardness of abrasives increases. Friction oscillation was also increased with hardness of the abrasives. However, the friction materials containing less abrasive particles produced stable friction films on the sliding surface. The transition between two-body and three body abrasion during sliding also played a crucial role in destructing the friction film on the pad surface and in determining various frictional properties.

• Tribology and Lubricants
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• 제30권3호
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• pp.177-182
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• 2014

To stop a high speed train running at the speed of 300 km/h, the disc brake for the train should be able to dissipate enormous kinetic energy of the train into frictional heat energy. Sintered pin-type metals are mostly used for friction materials of high speed brake pads. A pad comprises several friction pins, and the topology, length, flexibility, composition, etc. have a great influence on the tribological properties of the disc brake. In this study, the topology of the friction pins in a pad was our main concern. We presented the optimization of the topology of a railcar brake pad with nine-pin-type friction materials by thermo-mechanical contact analysis. We modeled the brake pad with/without a back plate. To simulate a continuous braking, the pad or friction materials were rotated at constant velocity on the friction surface of the disc. We varied the positions of the nine friction materials to compare the temperature distributions on the disc surface. In a non-optimized brake pad, the distance between two neighboring friction materials in the radial direction from the rotational center of the disc was not equal. In an optimized pad, the distance between two neighboring friction materials in the radial direction was equal. The temperature distribution on the disc surface fluctuated more for the former than the latter. Optimizing the pad reduced the maximum temperature of the brake disc by more than 10%.