• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.6
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• pp.130-141
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• 2000

The virbration characteristics of a passenger car steering column are studied by using a modal test and a finite element (FE) analysis. To verify the FE model and the results, an experiment using the impact exciting method is performed. Two types of the steering column in this study are considered as follows; (ⅰ) the non-tilt type steering column and (ⅱ) the upper-tilt type steering column. The experimental results are compared with those o the FE analysis, and it ti shown that the results agree with each other. The effects of various design parameters such as the bracket thickness, the column diameter on the natural frequencies are also investigated by FE analysis.

• Proceedings of the KAIS Fall Conference
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• 2011.12b
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• pp.639-642
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• 2011

본 논문은 LED 등기구 브라켓의 제품 생산방법의 개선에 관한 연구이다. 기존의 제품 생산시 레이저컷팅 ${\rightarrow}$ 절곡 ${\rightarrow}$ 도금 ${\rightarrow}$ 체결핀 가공 ${\rightarrow}$ 스프링 도금 ${\rightarrow}$ 조립 순으로 제작되어 LED 조명 등기구를 제작하였으나, LED 조명 등기구의 대량 생산이 요구되어 기존의 방법으로는 원가가 상승되어 고객이 원하는 가격에 생산할 수 있는 방법이 없어서 전용 금형을 제작하여 생산성 향상과 품질향상, 원가절감을 이루고자 하였다. 이에 본 논문에서는 LED 등기구 브라켓을 생산하기 위한 전용금형을 제작하여 생산시 개선전과 개선후의 결과에 대하여 연구하였다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.7
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• pp.22-28
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• 2019

In this study, as part of the subway braking system, the structural analysis was performed with the fatigue analysis by comparing subway brake disc and wheel-type brake. When structural analysis was performed, it was possible to verify that the wheel-type brake were higher than the brake discs in case of total deformation. As the same loading conditions were given to the subway brake disc and wheel-type brake, wheel-type brakes was shown to have more deformation than brake disk but lower damage than the subway brake disc. Comparing with each fatigue loading condition, the maximum fatigue life for 'Sample history' is found to be about 60 times longer than for 'SAE bracket history'.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.2865-2871
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• 2012

In this study, the fracture behaviour of DCB(double cantilever beam) specimen with aluminum foam composite materials is analyzed by simulation. By comparing the analysis results with two models of 25 mm and 40 mm, the model with thickness of 25 mm is weaker than 40 mm at fatigue life and damage. Two models are unfavorable at 'SAE Transmission' in case of nonuniform fatigue load and rainflow matrices are weakest at 'SAE Bracket history'. In damage matrices, the model with 25 mm of thickness is weaker than the model with 40 mm of thickness but the model with 40 mm of thickness relative damage possibility is higher than in case of 25 mm. As two models are safest at 'SAE Transmission', the relative damage becomes the lowest value from 1.1 to 1.8 %. The mechanical property can be investigated by applying these analyses results with the real composite structure bonded with adhesive and analyzing fracture behaviour.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.5906-5911
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• 2014

Currently, there are many processes of package assembly and inspections of real fields that examine whether a manufactured semiconductor can be operated regularly and can endure low humidity or high temperatures. As the inspection equipment of a semiconductor test handler picker has been used at the inspection process, these inspection equipment frames were modelled in 3D and these models were analyzed using 3 kinds of fatigue loadings. As the analysis result, maximum deformation occurred at the midparts of the frames at cases 1 and 2. Among the cases of nonuniform fatigue loads, the 'SAE bracket history' with the severest change in load became the most unstable but the 'Sample history' became the most stable. Fatigue analysis result can be used effectively with the design of an inspecting equipment frame of a semiconductor test handler picker to examine the prevention and durability against damage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.373-379
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• 2020

This study performed stress and fatigue life analysis of the damping hinge of a built-in side-by-side refrigerator that occurs when the door is opened to the maximum angle. An analysis of the initial design showed that stress concentration occurred at the corner between the cylinder and upper disk of the bracket pin, and the maximum stress exceeded the yield strength. The maximum stress location and the calculated fatigue life were consistent with the door opening-and-closing endurance test results for a prototype. Three cases of design improvement for the bracket pin were derived with the aim of reducing the stress concentration that appeared in the initial design. An analysis of the cases showed that inserting a fillet between the disk and the cylinder of the bracket pin reduced the stress and increased the fatigue life. Moreover, changing the disk into two steps was more favorable. In conclusion, the best design improvement was the case that the disk was changed to two steps and the fillet with a large radius was inserted. In that case, the stress was the smallest and the fatigue life was infinite.

• Journal of the Korean Society for Heat Treatment
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• v.27 no.6
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• pp.281-287
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• 2014

Microstructural and mechanical characteristics of Al-6Si-2Cu alloy for engine mount bracket prepared by gravity casting (as-cast) and die-casting (as-diecast) process have been investigated. For the microstructural characterization, the inductively coupled plasma mass spectrometry (ICP-MS), optical microscope (OM), scanning electron microscope (SEM) and electron probe microanalysis (EPMA) analyses are conducted. For the intermetallic phases, the X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) are also conducted with quantitative and qualitative analysis. Micro Vickers hardness and static tensile test are achieved in order to measure mechanical properties of alloys. Secondary dendrite arm spacing (SDAS) of as-cast and as-diecast show 37um and 18um, respectively. A large amount of coarsen eutectic Si, $Al_2Cu$ intermetallic phase and Fe-rich phases are identified in the Al-6Si-2Cu alloy. Mechanical properties of gravity casting alloy are much higher than those of die-casting alloy. Especially, yield strength and elongation of gravity casting alloy show 2 times higher than die-casting alloy. After shot peening, shot peening refined the surface grains and Si particles of the alloys by plastic deformation. The surface hardness value shows that shot peening alloy has higher value than unpeening alloy.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.64-76
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• 1997

This paper deals with development of brackets by using aluminum alloy sheets which is indispensable for weight reduction of autobody. The press formability of aluminum alloy sheet is estimated by means of tensile test, V bending test, sample manufacturing test and photograph of microstructure. The results show that the elongation, strength, work hardening exponent, plastic anisotropy coefficient of Al 6***series are better than those of Al 5***series, but for general press formability, Al 5***series are better than Al 6***series due to lower yield strength. Since most of mechanical properties of aluminum sheet are generally inferior to those of cold-rolled steel sheet, shape fixability and press formability of aluminum sheet are very poor. For making components of autobody by use of die for steel sheet application, it is essential that die should be nodified for least bending and stretching. With the modified die for aluminum, it could be possible to make brackets, the component of autobody. Microstructure of Al 5***series has fine grain and small the 2nd phase and that of Al 6***series has relatively coarse grain. Therefore, it seems that fine grain and small the 2nd phase of Al 5***series is one of the factor of lower yield strength, resistance to stamping work, formation of Luder's line.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4108-4114
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• 2010

The automation of the machining and manufacturing process of press die is designed to shorten the working time by avoiding unnecessary repetitive works and to obtain subject articles with standard quality. Automation as used in this paper includes 3-D die design, machining center, wire-cut electrical discharge machining, and drawing works. This paper deals with research work on the automation of the machining and manufacturing process of the press die after 3-D die design using the Irp bracket for the control box sensor. The research was conducted under the same setting as that of die design.

• Composites Research
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• v.32 no.5
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• pp.243-248
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• 2019

As demand of light weight in the automotive industry has increased, the cowl cross member has been investigated using various methods to change the material. Conventionally, a cowl cross member has been made of steel and aluminum, but recently researchers tested multi-material such as aluminum and plastic. We studied a new model of the cowl cross member made of composite and non ferrous materials. For products with a high degree of freedom in design, generally, the method of topology optimization is advantageous and for the partial bracket part of the cowl cross member had a degree of freedom in the design, a topology optimization is appropriate. Considering the characteristics of the cowl cross members, we need research to minimize the weight while having the performance of noise, vibration and harshness(NVH). Taking the mounting status of the product into consideration, we used an assembly model to optimize the cowl cross member. But this method took too much time so we considered simple cowl cross member assemble conditions using the direct matrix input method(DMI) with the Craig-Bampton Nodal Method. This method is capable of considering the status of the assembly without assembling the model, which reduced the solving time and increased the accuracy comparison with a cowl cross member without DMI.