• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1325-1326
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• 2013

• Journal of Auto-vehicle Safety Association
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• v.10 no.3
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• pp.38-44
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• 2018

Conventional brake system was used for passenger cars and SUV for a long time. However, the high performance brake system has strongly required because of increase of engine power and customer's favorites etc. In this paper, a new high performance brake system for Europe was proposed. For this system, the high performance caliper and disc were newly developed. The superiorities of the developed high performance brake system were verified via heat capacity, hydraulic stiffness, corrosion and harsh braking mode test. Also, the high performance caliper and disc for the light-weight were applied to AL-Alloy and can obtain the weight reduction effect of 2.9 kg per vehicle. Finally, a developed high performance brake system is expected to be used for realization of the high performance at the same platforms.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.3
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• pp.693-699
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• 2024

The main cause of scattering dust generated by transportation equipment such as automobiles was largely due to exhaust gas from internal combustion engines in the past, but it was generally recognized that non-exhaust causes such as abrasion of the tires or brake pads were low. Accordingly, scattering dust generated by exhaust gas has consistently existed in many studies, such as technological progress and related regulations, but research on non-exhaust is relatively insignificant, and the need for research on scattering dust generated by non-exhaust is emerging. In this study, a dust collector that can be easily mounted on a caliper to collect scattering dust generated by pad wear during the brake operation of an automobile was manufactured. In this study, we developed a dust collector that is easy to mount on calipers to collect scattering dust caused by pad wear during brake operation of automobiles. According to the installation of the manufactured dust collector, the performance of scattering dust by brake operation and the temperature change characteristics of calipers according to the structure of the dust collector were evaluated.

• Tribology and Lubricants
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• v.27 no.4
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• pp.204-208
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• 2011

Yaw brakes are used in wind turbines to control the orientation of blades to be perpendicular to the wind. These devices are very important machine elements because they are closely related to the overall efficiency of wind turbines. One unit of yaw brakes is composed of a friction pad and a caliper. In this study, a tangential force between the friction pad and the disk is calculated when the brake is acting in 750 kW wind turbine. Then, stress distribution and the deformation of the caliper are calculated using a finite element analysis. An experimental equipment is also developed to verify the exactness of calculated results. The analytical and experimental results are presented and discussed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.10
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• pp.749-755
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• 2014

The analytical-finite element(FE) squeal model is applied to investigate the squeal propensity associated with contact stiffness of the disc brake system. The system contact stiffness is incorporated into the perturbed equations of motion in the analytical manner where the brake components are modeled by FE method. The results show that the contact stiffness of the friction material and the contact stiffness between the pads and caliper are the influential factors on the squeal propensity. Particularly, the modal instability of the 3200 Hz squeal mode drastically changes with respect to the contact stiffness between the pads and caliper.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.12
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• pp.1351-1358
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• 2014

This study numerically simulates brake squeal and validates it experimentally by using a lab-scaled brake dynamometer. The system frequencies of the disc brake are traced with respect to the brake pressure by using a modal test and FEM. Then, the squeal frequencies measured from the brake dynamometer are found to correspond to the brake system mode with the dominant displacement of the caliper and pad. Furthermore, a complex eigenvalue analysis conducted using the finite element model confirms that the caliper mode generating the rotational displacement of the pad becomes unstable owing to the negative friction-velocity slope.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.607-612
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• 2004

Disc brake noise continues to be a major concern throughout the automotive industry despite efforts to reduce its occurrence. Eliminating vibrations during braking is an important task for both vehicle passenger comfort and reducing the overall environmental noise levels. There are several classes of disc brake noise, the major ones being squeal, judder, groan, and moan. In this study, analytical model for moan noise of rear disk brake is investigated. Modeling of the disc brake assembly to take account of the effect of different geometrical and contact parameters is studied through the use of multi-body model. The contact stiffness of the caliper and torque member plays an important role in controlling brake vibration. Therefore, a suitable material pair at the caliper/body contact has been made. An ADAMS model of a rear disc brake system was integrated with a flexible suspension trailng arm from MSC/NASTRAN. A fully non-linear dynamic simulatin of brake system behavior, containing rigid and flexible bodies, was performed for a Prescribed set of operating conditions. Simulation results were validated using data from vehicle experimental testing.

• Tribology and Lubricants
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• v.27 no.5
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• pp.269-274
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• 2011

The purpose of this paper is to study and analyze the improvement method for the failure examples including the vehicle brake system in actual field. It was verified that the indicator plate of pad wear scratched the brake disk because of wearing after displacement of non- identification parts pad. The caliper of other vehicle was installed with brake system verified the phenomenon produced groove in center point because of one side wear when the pad was not fully contacted with the rub disk by other action surface pressure and pad action condition. It verified that the crack phenomenon fatigue was produced by brake thermal deformation because of decreasing the thickness by grinding to modify the non-uniformed wear of brake disk. It verified that the friction sound was produced by the friction phenomenon because of non-uniformed contact of lining and an alien substance with inner of the drum and lining braking by crack phenomenon with brake drum surface.

• Journal of Auto-vehicle Safety Association
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• v.12 no.2
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• pp.7-13
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• 2020

Recently, there is a big issue of downsizing on brake system according to fuel efficiency and regenerative braking cooperation control. Especially, small cars have improved in a variety ways such as electric vehicle and smart car compared to previous small cars. So, small brake system is strongly required in the car industry. A new small brake system for light compact vehicles was proposed in this paper. For this system, the solid type disc and caliper were newly developed. And the important design factors were considered to reduce brake size. First, we calculated the temperature rise of disc through heat capacity formula and CAE analysis. Second, we analyzed the housing and carrier stiffness of caliper to select the reasonable condition. Finally, the superiorities of the developed brake system were verified by heat capacity, consumption liquid level, braking feeling, judder, wear test and regenerative braking cooperation control analysis. A developed brake system is expected to be useful for brake system of light compact platform.

• Tribology and Lubricants
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• v.13 no.4
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• pp.10-17
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• 1997

The present study describes an experimental investigation of temperature fluctuations associated with thermal instability. Surface temperatures of brake disk and pad were monitered at various locations in a caliper type brake system during drag braking conditions. It was found that the thermal instability appeared in pad more seriously than in disk. The temperatures at various circumferential positions fluctuate synchronously, whereas the center temperature fluctuates with 180$^{\circ}$ phase difference from the outer and inner radius temperatures. The temperature and amplitude of the temperature perturbations are increased due to the increase of contact area in the center location. It was also found that the thermal instability was dominantly determined by the increase of rotation speed and pressure. And the modification of ventilation path could retard the onset of thermal instability.