• 소성∙가공
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• 제18권7호
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• pp.538-543
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• 2009

The cowl cross bar of an automobile is a frame component that is installed inside the cockpit module to provide a guide surface, to which functional components for electricity and air condition are attached. In the recent years, the geometries of cowl cross bars are getting more complex in order to meet the demands of a wide variety of embedded functional components and the reduced weight of frame parts with enhanced mechanical and noise/vibration characteristics. There for, welding processes between tubes with different diameters are widely conducted while the welded parts are experiencing various problems such as undermined appearance, low production efficiency and poor mechanical characteristics. Therefore, this paper seeks to develop an one-piece forming process which eliminate welding process for the cowl cross bar by applying the tube drawing process. However, it was predicted that a conventional tube drawing can not be applied directly to the current part since the area reduction ratio of the drawing process reaches 51.7% which exceeds the general limiting value. Therefore, in this study, a combined drawing process which adds a compressive force to a tensile force of the conventional drawing process was proposed and 2-stage drawing process was designed by using CAE analyses. In addition, drawing tryouts were carried out by using the manufactured combined drawing machine in order to verify the designed process.

• 한국염색가공학회지
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• 제35권1호
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• pp.29-41
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• 2023

This study is about a hybrid lightweight cowl crossbeam structure with high rigidity and ability to absorb collision energy to support the cockpit module, which is an automobile interior part, and to absorb energy during a collision. It is a manufacturing process in which composite material bracket parts are inserted and injected into existing steel bars. When considering the mounting condition of a vehicle, the optimization of the fastening condition of the two parts and the mechanical properties of the composite material is acting as an important factor. Therefore, this study is about a composite material having a volume content of Polyamide(PA) and Glass Fiber used as a composite material for a composite material-metal hybrid cowl crossbeam. As a result of analyzing the physical properties of the PA/GF composite material, experimental data were obtained that can further enhance tensile strength and flexural strength by using PA66 rather than PA6 used as a base material for the composite material. And based on this, it contributed to securing the advantage of lightening by using high-stiffness composite material by improving the high disadvantage of the weight of the cowl crossbeam material, which was made only of existing metal materials.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.236-239
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• 2009

Cowl cross bar, a component of automotive cockpit module, has been manufactured by using welding processes of several tube parts with different diameters. However, in order to reduce costs and increase the quality, it is required to develop a new production method to manufacture the cowl cross bar as one-piece In this study, therefore, eliminating the welding process, tube drawing process which is one of metal forming processes was designed by using combined drawing technique. In addition, the selectable range of area reduction ratio was defined as a design guideline and the designed process sequence was verified by finite element analysis.

• 소성∙가공
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• 제25권5호
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• pp.332-337
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• 2016

The automobile cowl cross bar which is a backbone frame part holding electrical and air conditioning components inside the cockpit module has been designed with more complex geometries recently due to demands of its enhanced functions and reduced weight of frame parts. The traditional manufacturing process using welding between tubes with different diameters shows several problems such as poor mechanical characteristics and appearance, etc. Therefore, in this study, one-piece manufacturing processes which can eliminate the welding process were developed by applying the rotary swaging process. CAE analyses were conducted to examine the feasibility of the process and prototypes were manufactured by using a rotary swaging machine with 4 split rotating dies and 12 head rollers. Bending tests of the manufactured prototypes confirmed that the rotary swaging process gives better mechanical properties comparing with the conventional processes.

• 한국자동차공학회논문집
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• 제10권6호
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• pp.166-170
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• 2002

A hybrid structure composed of magnesium and steel is Instrument Panel structure used for the basement of cockpit module components. For that reason, A hybrid structure has to be designed for satisfying components assembly design facility and styling. There are various models of If like steel structure assembly, however having been applied normally, but magnesium structure assembly selected far saving weight down. This paper introduces a hybrid structure having advantages between steel and magnesium structure and presents a CAE technical solution based on a development project. furthermore, it provides desired direction of the future development is suggested.

• 한국융합학회논문지
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• 제8권12호
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• pp.275-281
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• 2017

카울크로스바는 차체의 계기판 후면에 설치되는 보강 부품으로서 최근 부품의 기능 개선 및 차량 경량화의 요구로 인하여 점차 복잡한 형상의 제품이 개발되고 있다. 특히, 제품 좌우의 지름과 두께가 서로 다른 경우에 이직경 파이프의 용접을 통하여 제품이 생산되는데, 외관 품질 및 기계적 성질의 저하 문제가 지속적으로 제기되어 소성 가공을 이용한 일체화 성형 기법의 개발이 요구되고 있다. 본 연구에서는 좌우 형상이 서로 다른 직선형 카울크로스바에 대한 일체화 성형 기법으로서 복합 인발 공정과 스웨이징 공정을 개발하였으며 기계적 성질 및 생산비의 관점에서 개발 공정들을 비교하고자 한다. 결론적으로 일체화 성형 제품이 기존 용접 제품에 비해 우수한 굽힘 강도를 보이며 스웨이징 공정을 사용할 경우 보다 저렴한 비용으로 생산이 가능함을 알 수 있었다.

• 한국산학기술학회논문지
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• 제19권8호
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• pp.25-31
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• 2018

본 연구에서는 카울 모듈의 성형 시 최적 설계 공정을 유한요소해석을 통해 도출하는 방안을 제시하였다. 소재 인장시험 및 성형성 평가와 같은 기계적 물성 평가를 통해 성형 해석의 주름 및 크랙 발생을 사전에 파악하고 이를 개선하기 위한 공정 설계 변경을 통해 최적 설계 방안을 도출하였다. 또한 제진성 향상이 필요한 카울 로워 패널에 패치워크를 적용을 통해 카울 모듈의 강성 증대 및 제진 특성 향상을 고유진동수 측정 시험과 해석을 통해 확인하였다. 해석 결과, 실러 패치워크 기술 적용에 따른 1차 고유진동수가 향상됨을 알 수 있었고, 이는 강성 및 제진특성 증대와 관련있다고 볼 수 있다. 실러 패치워크 적용 시 공정수 감소를 위해 성형 전 로워 패널 블랭크에 패치워크 블랭크를 점용접으로 접합시켜 성형하므로, 성형 후 패치워크 패널의 위치가 점용접 조건에 따라 달라진다. 이를 위해 점용접 위치에 따른 성형 해석을 실시하여 결과를 바탕으로 최적 공정 설계를 도출하였다. 스탬핑 공법을 이용한 타부품의 적용을 위해 성형 해석 기법을 구축하여 다양한 제품 설계에 도움이 될 것으로 판단된다.