• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.118-124
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• 2004

To investigate the mechanics of brake squeal noise, the sound and vibration of an actual brake system was measured using a brake dynamometer. The experimental results show that disk run-out due to the misalignment of brake disk varies with brake line pressure and becomes the important factor of brake squeal noise generation. Also, it was confirmed that the frequency of the squeal noise equals to the natural frequency of the disk bending mode.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1690-1695
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• 2003

In order to investigate the mechanism of brake squeal noise, the sound and vibration of an actua1 brake system were measured using a brake dynamometer. The experimental results show that disc run-out varies with brake line pressure and the factor of squeal generation is the run-out due to the misalignment of brake disk. A three degrees of freedom friction model is developed for the disk brake system where the run-out effect and nonlinear friction characteristic are considered. The results of numerical analysis of the model agree well with the experimental results. Also, the stability analysis of the model was performed to predict the generation of brake squeal due to the design parameter modification of brake systems. The results show that the squeal generation depends on the nm-out rather than the friction characteristic between the pad and the disk of brake.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.269-270
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• 2006

Brake noise is classified according to frequency territory: judder, groan and squeal. Squeal noise of disk brake is a noise and self excited vibration with frequency of $1{\sim}10Khz$ caused by the friction force between the disk and the pad of the automobile. Passengers in a vehicle feel uncomfortable. It causes unstable characteristic to the brake system when you try to stop the vehicle. Thus this study aims to find in which conditions the vehicles are stable during the braking hour and find ways to decrease a squeal noise and the vibration by measuring various factors including squeal noise and self excited vibration between the pad and disk brake system during the braking hour. From the result the countermeasure for a squeal noise and a vibration decrease is established. Also the analyzed data is found to be useful and can be applied to the actual brake model.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.3
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• pp.41-47
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• 2005

This paper deals with a squeal noise in a brake system. It has been proved that the squeal noise is influenced by the angular misalignment of a disk, disk run-out, with the previously experimental study. In this study, a cause of the noise is examined by using FE analysis program(SAMCEF) and numerical analyses with a derived analytical equation of the disk based on the experimental results. The FE analyses and numerical results show that the squeal noise is due to the disk run-out as the experimental results and the frequency component of the noise equals to that of a disk's bending mode arising from the Hopf bifurcation.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.595-600
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• 2004

This paper deals with a cause analysis of a squeal noise in a brake system. It has been proved that the squeal noise is influenced by the angular misalignment of a disk, disk run-out, with the previously experimental study. In this study, a cause of the noise is examined by using FE analysis program(SAMCEF) and numerical analyses with a derived analytical equation of the disk based on the experimental results. The FE analyses and numerical results show that the squeal noise is due to the disk run-out as the experimental results and the frequency component of the noise equals to that of a disk's bending mode arising from the Hopf bifurcation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.8 s.113
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• pp.830-839
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• 2006

The phenomenon of squeal noise in the disk brake system has been, and still is, a. problem for the automotive industry. Extensive research has been carried out in an attempt to understand the mechanism that causes squeal noise and In developing design procedures to reduce squeal noise to make vehicles more comfortable. In this paper, the study on the analysis of squeal noise is performed by using computer aided engineering to design the anti-squeal noise disk brake system. The first part describes the chassis dynamometer and the testing procedure, and second part explains the finite element model and the complex eigenvalue analysis. Finally, it is shown that the proposed squeal noise analysis could be useful to investigate the design parameters that affect the squeal noise characteristics.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.10
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• pp.1042-1048
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• 2008

Disc brake noise is an important customer satisfaction and warranty issue for many manufacturers as indicated by technical literature regarding the subject coming from Motor Company. This research describes results of a study to assess disk brake squeal propensity using finite element methods and optimal technique (Kriging). In this study, finite element analysis has been performed to determine likely modes of brake squeal. This paper deals with friction-induced vibration of disc brake system under contact friction coefficient. A linear, finite element model to represent the floating caliper disc brake system is proposed. The complex eigen-values are used to investigate the dynamic stability and in order to verify simulations which are based on the FEM model. In this paper, Kriging from among the meta-modeling techniques is proposed for an optimal design scheme to reduce the brake squeal noise.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.126-134
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• 2007

Although there has been substantial research on the squeal noise for the automotive brake system, robust design issues with respect to control factors equivalent to design variables in optimization, noise factors due to system uncertainties, and signal factors designed to accommodate a user-adjustable setting still need to be addressed. For the purpose, the robust design applied to the disk brake system has been investigated by DOE (Design of Experiments) based Taguchi analysis with dynamic characteristics. The specific goal of this methodology is to identify a design with linear signal-response relationship, and variability minimization. The finite element models of the disk brake assembly have been constructed, and the squeal noise problems have been solved by complex eigenvalue analysis. As the practical robust design to reduce the brake squeal noise, material properties of pad, disk, and backplate, thickness and geometry of pad are selected as control factors, material properties of pad and disk, and the contact stiffness have been considered as noise factors, and friction coefficient between pad and disk is chosen as a signal factor. Through the DOE based robust design, the signal-to-noise ratio and the sensitivity for each orthogonal array experiment have been analyzed. Also, it has been proved that the proposed robust design is effective and adequate to reduce the brake squeal noise.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.963-963
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• 2008

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.236-240
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• 2005

This paper deals with friction-induced vibration of disc brake system under constact friction coefficient. A linear, finite element model to represent the floating caliper disc brake system is proposed. The complex eigenvalues are used to investigate the dynamic stability and in order to verify simulations which are based on the FEM model, The comparison of experimental and analytical results shows a good agreement and the analysis indicates that mode coupling due to friction force and geometric instability is responsible fur disc brake squeal. And the Front brake system reduced the squeal noise using design of experiment method(DOE). This helped to validate the FEM model and establish confidence in the simulation results. Also they may be useful during real disk brake model.