• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.05a
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• pp.65-66
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• 2010

To improve the gear noise quality, gear tooth grinding machine are widely used in automotive industry. While using the gear profile grinding machine to improve the gear tooth quality of the transmission, several defects such as chattering, tooth waves that cause the gear noise occasionally happened. But it is very difficult to solve that problem, because there is no one who knows the setting up the optimal grinding condition appropriately. The abnormal manufacturing conditions which make the gear noise make the engineer to spend a lot of time, effort, and money. Due to demands for solving the serious abnormal gear noise happened in the new FF 6th stage automatic transmission in the mass product stage, the vibration checking process in the worm wheel axis, work rotation and fixed axis of the grinding machine were adapted to find the root causes. As a result, gear profile wave are affected by the work rotation axis's unbalance which is caused by worm wheel feeding speed. And a primary and the secondary grinding feeding speed, cutting oil, work fixed forces are also proved as the important factors. After setting up the grinding condition reported in this paper, it was adapted successfully to the grinding machine to manufacture the new FF 6th speed automatic transmissions' output gear. The gear noise was dramatically disappeared and the process and results will offer good guides to the engineers who manufacture the gear with the grinding machine.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.7
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• pp.665-671
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• 2010

To improve the gear noise quality, gear tooth grinding machine are widely used in automotive industry. While using the gear profile grinding machine to improve the gear tooth quality of the transmission, several defects such as chattering, tooth waves that cause the gear noise occasionally happened. But it is very difficult to solve that problem, because there is no one who knows the setting up the optimal grinding condition appropriately. The abnormal manufacturing conditions which make the gear noise make the engineer to spend a lot of time, effort, and money. Due to demands for solving the serious abnormal gear noise happened in the automatic transmission in the mass product stage, the vibration checking process in the worm wheel axis, work rotation and fixed axis of the grinding machine were adapted to find the root causes. As a result, gear profile wave are affected by the work rotation axis's unbalance which is caused by worm wheel feeding speed. And a primary and the secondary grinding feeding speed, cutting oil, work fixed forces are also proved as the important factors. After setting up the grinding condition reported in this paper, it was adapted successfully to the grinding machine to manufacture the new automatic transmissions' gear. The gear noise was dramatically disappeared and the process and the results will offer good guides to the engineers who manufacture the gear with the grinding machine.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.34-44
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• 1997

This study presents the recursive constraint bounding(RCB) method to reduce the cycle time in internal cylindrical plunge grinding process. This method can cope with process noise as well as modeling bias. The main features of RCB method are its utilization of measurements at the end of each cycle and its use of monotonicity analysis for determining the extremes of bias and noise. This method is investigated in simulation and evaluated by experiment in internal cylindrical plunge grinding operation. The results from simulation and experiment show that it is effective in reducing cycle time in spite of modeling uncertainty in the forms of process noise and modeling bias.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.745-750
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• 2014

The chatter vibration in the machining process plays bad role in machining quality such as high roughness as well as tool life and machine failure. And the grinding process under this risk in the fully automated factory is exposed to the unexpected mass machining quality problem. Studying the vibration signal of the hub bearing grinding process, the reason of chatter vibration was explained with the specific machining pattern of chatter. And this study suggests the chatter detecting method in the production line, which is monitoring the peak acceleration level around the natural frequencies of the specimen, and calculating kurtosis value by assuming the chatter is related to the resonance of the specimen. The suggested method was applied to the vehicle hub bearing grinding process and proved good to detecting the chatter induced machining quality problem.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.283-289
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• 2004

Rail defects(Corrugation, shelling, etc) are occurred by the Rail with wheel contact stress. Rail grinding is maintaining of optimal rail profile to use special rail grinding machine to remove rail defect. The benefits of rail grinding enforcement, improve track safety, improve track steering and rail life, improve ride comfort and reduce noise, etc. Actually when rail grinding plan apply to field track, we should consider a lot of function before determination, such as grinding method, grinding pass number, removing metal volume, etc. because each track has various characteristics. Therefore it is important that the determination of rail grinding strategy for optimum and economic before enforcement.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.54-59
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• 2012

This study dealt with effect of the grinding in SCM420H planetary gears. The hardness, tooth profile, lead and roughness of the gear surface can be improved by grinding process. Therein, the grinding techniques are widely used especially as one of the physical surface improvement methods. As the results, the gear grinding process reduced vibration and noise, and increased the life of the gear. And the gear grinding improved the surface of gear tooth in a short time and low cost, thus, it is a very important process in manufacturing industry. But nowadays, it is hard to find the detail information of gear grinding process. The test piece is a planetary gear which is used in the industrial machine. The manufacture process of the test piece contains hobbing, shaving, carburizing and grinding. This study investigated the effect of the grinding process to the physiognomy and the fatigue strength of test piece which was made by SCM420H.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4732-4737
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• 2011

A standing grinder with a vacuum dust collection, which works grinding a surface and collecting dust occurred simultaneously, is needed to clean the surface before painting, or to remove a weld bead burr in the industrial field. In recent it trends to be compact and potable with high grinding and dust collection power, and low noise. As increasing these grinding and dust collection power, the noise and weight of standing grinder occurs an important problem. To solve these problem, an efficient cyclone separator was designed and developed by Ansys-CFX analysis and experiments. A weight of the developed grinder part was 5.9kg, which can be easily handled on standing by workers. and a noise level of the developed prototype was measured 69.9 dB(A).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.516-519
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• 2004

As the optical communication industry is developed, the demand of optical communication part is increasing. ZrO$_2$ ceramic ferrule is very important part which can determines the transmission efficiency and information quality to connect the optical fibers. In general ZrO$_2$ ceramic ferrule is manufactured by grinding process because the demands precision is very high. And the co-axle grinding process of ZrO$_2$ ceramic ferrule is to make its concentricity all of uniform before centerless grinding. This paper deals with the analysis of the process parameters such as grinding wheel speed, grinding feedrate and regulating wheel speed as influential factors, on the concentricity and surface finish developed based on Taguchi's experimental design methods. Taguchi s tools such as orthogonal array, signal-to-noise ratio, factor effect analysis, etc. have been used for this purpose optimal condition has been found out. Thus, if possible be finding highly efficient and quality grinding conditions.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.6
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• pp.36-43
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• 2022

Automobile brake discs are a major part of automobiles that are directly related to driver safety, and prevention of judder and squall noise is very important. This phenomenon occurs for complex reasons such as the precision and assembly of the brake module, and the material of the brake disc. The purpose of this study is to analyze the effect of the grinding wheel's grain size on the grinding conditions when machining cast iron, the material of the brake disc, and to derive the optimal grinding conditions through this.

• Journal of Auto-vehicle Safety Association
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• v.7 no.2
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• pp.19-24
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• 2015

Ferritic Nitro Carburizing (FNC) cast iron brake discs is known to improve corrosion resistance and brake creep groan noise as well as prevent corrosion-induced pulsation. But, it is necessary to treat honing machining on braking surface to avoid grinding noise during braking.