• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.486-491
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• 2013

Creak noise is kind of scratching noise which is usually generated in drum brake system on the vehicle. When driver brakes vehicle or applies parking lever, drum brake shoe moves to the drum side to stop the vehicle. And at that time, moving shoe scratches backing plate ledge surface, and that makes scratching noise in special condition. This study presents how we can generate creak noise in the laboratory and how we can reduce it by experimental approach. Through several and various type of tests, we could generate creak noise with damage on ledge area of the backing plate in the lab and we verified tab type shoe design can reduce this scratching noise. As a result of this study, we notified how creak noise happens in the vehicle, and that tab type design shoe has good performance of ledge area damage based on lab test(rig & dynamometer equipment), and that this can reduce potential risk of creak noise in the field.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.139-144
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• 2020

In this study, a simulation analysis on the drum itself and the brake was examined. And the analysis results were obtained by investigating the thermal analysis results and the durability through structural analysis. Through the thermal stress and structural analyses on the lining under the force due to the brake cylinder, the drum inside under the force due to the expansion of the lining and the drum under the force due to the rotation of the axis, it was confirmed at which part the amounts of equivalent stress and deformation became large. If applied to the brake disc design by combining the results of this study, it is considered to be large utilization at increasing the prevention against the thermal deformation and its durability. The results of this study can be usefully applied to the durability design that can withstand the thermal stress in the drum brake. By applying the durability analysis at the seam of railroad track by season, this investigation result is seen to be favorable as the convergent research applied to the aesthetic design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.707-710
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• 2001

Brakes are one of the important safety parts in cars. The requirements of brakes in performance, in comfort, and working lifetime are high. This paper presents the static analysis on the stress and temperature of a automotive drum brake. The particular interest is the distribution of the contact pressure between brake lining and drum. The problems to be solved are the effects of friction coefficient, actuation force, temperature, and brake component's stiffness. The contact problem includes friction, and is solved using the ABAQUS.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.9
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• pp.111-116
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• 1998

The squeal of drum brakes was investigated numerically and experimentally. Modal testings were performed for shoes, drums, backing plates and their assemblies. In order to predict the squeal phenomena, stability analysis was performed based on a simplified self-excited vibration model. Based on modal testings, the dynamic properties of the brake elements and the parameters used in this analysis were determined. The geometries of shoes and drums were also considered. The result shows that the modification methods of the shoe and the drum design are feasible for noise reduction.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.733-736
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• 2002

This study was carried out to investigate the braking performances associated with the friction coefficients and temperature fluctuations. Friction coefficient stability and maximum temperature of brake drums, made of an Al-MMC and conventional cast iron, were tested by the inertial brake dynamometer during 15 braking operations. Also the temperature distribution was analyzed by the finite element analysis(FEA). In this experiment, both lower temperature rise near the drum surface and less variation of friction coefficient, compared to those of cast iron, were observed with Al-MMC drums during braking operations.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.3
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• pp.10-18
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• 1993

• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.65-71
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• 2008

This paper presents a transient heat transfer analysis of a drum brake shape. The transient heat transfer analysis of automotive drum brakes with frictional contact is performed by using the finite element method. The drum brake type studied in the page is the internally expanding one in which two shoes fitted externally with frictional material are forced outward against surface a rotating drum on the wheel unit. In this case, the braking power is produced by the friction force between a drum and a lining, and is converted into heat. The brake drum has constant material properties. The air inside the drum has temperature-dependent thermal conductivity and enthalpy. Radiation effects are ignored. The result explains the reason why hair crack and cause of drum failure occur. The temperature of drum is in proportion to the drum thickness and nonlinear changes at every points of drum. It's necessary for the decrease of the drum temperature to make the air inside drum flow.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.1
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• pp.65-70
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• 2010

The effect of austempering treatment on the dynamic properties of a brake drum was investigated to primarily evaluate the potential damping advantage of an AGI (austempered gray iron) drum over a PGI (pearlitic gray iron) drum. This investigation provides valuable information for brake noise reduction since the brake drum is most often the outstanding component that generates the noise of the brake assembly. Test results show that the AGI drum provided slightly larger damping values than the PGI drum for the first few major resonances observed. A finite element model of a drum was also developed to aid in studying its dynamic behavior. A good correlation was obtained between the analytical results and the actual measurement data.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.181-185
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• 2001

This paper deals with the dynamic stability of a disc brake pad taking into account of its shear deformation and rotary inertia. A brake pad can be modeled as a beam like model subjected to distributed friction forces and having two translational springs. The study of this model is intended to provide a fundamental understanding of dynamic stability of drum brake pad. Governing equations of motion are derived from extended Hamilton's principle and their corresponding numerical solutions are obtained by applying the finite element formulation. The critical distributed friction force and the instability types are investigated bt changing two translational spring constants, rotary inertia parameter and shear deformation parameter. Also, the changes of eigen-frequencies of a beam determining instability types are investigated for various combinations of two translational spring constants.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.433-436
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• 2000

For a new design of a automotive brake system, it appears to be very important to examine the temperature and thermal stresses distribution in the brake drum. In the direct measurement of them, however, a number of difficulties are involved. In this study, simulation on temperature and thermal stress distributions in an A1-MMC brake drum of a commercial vehicle during 15 braking operations was carried out using the finite element analysis(FEA1. The effect of a circumferential fin near open end of the brake drum on the temperature rise and stresses was also examined.