• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.877-881
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• 1996

승용차나 소형승합차에는 현가장치의 스프링으로 코일스프링을 많이 사용하고 있으며 최근 들어 승차감의 상을 위해 변위의 증가와 함께 스프링 정수가 증가하는 경화 특성 스프링(hardening type spring)을 많이 채택하고 있는데, 이 특성을 나타낼 수 있는 방법 중 하나가 등반경-테이퍼 소재의 코일스프링이다. 이 논문에서는 주어진 차량조건으로부터 이상적인 스프링 특성곡선을 계산하고 이 곡선을 분할하여 직선의 연결로 근사시켜 분할한 수만큼의 직선적 특성의 스프링으로 직렬 연결되어 있다고 가정하여 이 곡선에 근접된 특성을 가지는 등반경-테이퍼 소재 코일 스프링의 설계방법을 제시하고자 한다.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.3
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• pp.151-162
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• 2000

This study is concerned with computerized multi-level substructuring methods and stress analysis of coil springs. The purpose of substructuring methods is to reduce computing time and capacity of computer memory by multiple level reduction of the degrees of freedom in large size problems that are modeled by three dimensional continuum finite elements. In this paper, the spring super element developed is investigated with tension, torsion, and bending of a cylindrical bar in order to verify its accuracy and efficiency for the multi-level substructuring method. And then the algorithm is applied to finite element analysis of coil springs. The result demonstrates the validity of the multi-level substructuring method and the efficiency in computing time and memory by providing good computational results in coil spring analysis.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.102-107
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• 2004

Suspension part should have enough endurance during its lifetime to protect passenger. Therefore, the coil spring is one of the major suspension part of an automobile. Corrosion fatigue strength of the coil spring depends on many factors including mechanical and environmental properties. In this paper, residual stresses by shot peening was analyzed using finite element analysis and evaluated its effect on corrosion fatigue strength.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.673-675
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• 2002

In this paper. the lumped electrical circuit approach of mass/spring system is used to model the mechanical aspects according to the frequency. Therefore, the mass/spring system can be dealt with here and linked with the equivalent circuit of electric linear oscillatory actuator(LOA). Analysis models are double-coil type linear compressor for stirling refrigerator. The compressor consists of the moving coil LOA, piston, and spring. The electro-mechanical system with mass and spring can be represented using the lumped electrical circuit. We present the system impedance and dynamics of moving coil linear compressor.

• The korean journal of orthodontics
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• v.21 no.2 s.34
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• pp.353-366
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• 1991

This study was performed to analyze the effects of forces to the alveolar bone by various molar uprighting spring such as helical uprighting spring. T-loop spring, Modified T-loop spring and open coil spring. The simplified two-dimensional photoelastic model was constructed with a lower left posterior quadrant containing the second molar, the first and second premolars and the canine, with the first molar missing. Several molar uprighting springs were fabricated from 0.017 by 0.022 inch blue Elgiloy and applied to the photoelastic model. Two-dimensional photoelastic stress analysis was performed, and the stress distribution was recorded by photography The results obtained were as follows; 1. In all the kinds of the springs, the center of rotation of the mandibular second molar was oserved at the apical 1/5-1/6 between the alveolar crest and the root apex. 2. In all the kinds of the spring, the stress induced in the mesial root surface of the mandibular second molar was relatively homogeneous but there was some difference in the magnitude of the stress. 3. In the kinds of the springs, the distal crown tipping moment of the second molar was increased in turn as open coil spring, helical uprighting spring, T-loop spring, and modified T-loop spring. 4. The largest extrusive force was occured in the T-loop spring, intrusive force was occured in Modified T-loop spring only, and the largest distal tipping force was occured in open coil spring. 5. In the T-loop spring with activation, the stress induced in the mesial root surface of the second molar was increased gradually from the root apex to the alveolar crest and highly concentrated in the alveolar crest.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.123-124
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• 2008

• Corrosion Science and Technology
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• v.16 no.6
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• pp.298-304
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• 2017

Coil spring steels from the automobile suspension part after field exposure for 10 years and those after anti-corrosion validation test in proving ground of 5,000 ~ 10,000 km were examined for corrosion damages. Partial loss of paint, accumulation of corrosion product, and cracking of paint and superficial material were observed. The surface and subsurface region of spring steels had compressive residual stress and high hardness by shot peening. The surface hardness values of the specimens were 620 ~ 670 Hv. They were 60 ~ 80 Hv higher than those of the samples taken from the middle part of the spring. The maximum compressive stress was -916 ~ -1208 MPa measured at depth of about $100{\mu}m$. Electrochemical impedance spectroscopy showed that the resistances of charge transfer and the paint layer of the spring steels ranged from several tens to millions ${\Omega}{\cdot}cm^2$. The resistance of the field samples was much higher than that of the proving ground samples used in this study, implying that the proving ground test condition would be more corrosive than the field environment.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.1831-1838
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• 1991

The deformation of coil spring with noncircular section, which is used in the engine valve of automobiles under the applied load is usually accompanied by sectional warping and additional displacements of geometric center. In this study the isoparametric beam element formulations are modified and expanded to consider these two effects. To verify these formulations, simple torsion tests are made and compared with the analysis results. For the case of the zero-pitch spring, the stress distributions of oval and circular section are coincided with those of the analysis using the solid elements. Cylindrical coil springs with oval section are analyzed. These results are agreed with those of Nagaya.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.4
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• pp.355-360
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• 1983

This paper deals with fatigue behavior of ion-nitrided coil spring. It is found that fatigue limit can be significantly increased by ion-nitriding. Ion-nitribed specimen which is treated at 550.deg. C for 5 hours improves in the fatigue limit by 30 percent in comparison with that of non-nitrided specimen. On the other hand, the value of spring constant K has nothing to do with nitriding time and temperature in this experimental range. Besides fatigue behavior, the following effects are discussed such as compound layer, diffusion layer, hardness distribution and their relations.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.263-265
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• 2015

In this paper, a coil spring of the suspension components of the car is calculated through FEM(Finite Element Method) when a portion of the one is applied by an external load. we analyze the situation by using 'Large Deformation Analysis SW' in the EDISON structural dynamics server. Results of the analysis are about a displacement of the upper spring after deformation and total mass, and we use them to calculate the spring constant and maximum von-Mises stress by using Hooke's law and von-Mises stress equation. Finally, we visualize the relationship between the calculated spring constant and the mass through graphs and this data are beneficial for industries related to the spring.