기계식 프레스를 이용한 고정밀 리클라이너의 기어성형 제조공정 = Manufacuring process of gear forming for high precision reclineer by Mechanical press

다국어 초록 (Multilingual Abstract)

Fine blanking is a conventional process of press shearing which can produce the thick sheet metal of the finished surface and the close dimensional accuracy over the whole material thickness in the single blanking operation. A seat recliner that connects the seat back with the seat frame has a function of adjusting the seat back angle. In general, an external gear which plays an important role in automotive seat recliner is manufactured by fine blanking process. On the other hands, mechanical press to replace hydraulic fine blanking press with low stroke per minutes (SPM) is well used for high productivity in the automotive industry. However, the use of mechanical press has a limitation in manufacture of the part with high dimensional accuracy. Therefore, development of new forming process is required to manufacture an external gear with high dimensional accuracy by mechanical press. In this study, the effect of the size of blank, vee-ring indenter and the flow restriction die (FRD) on dimensional accuracy and damage in an external gear were investigated by 3-dimensional finite element analysis. FE-simulation results for different conditions indicated that FRD has high dimensional accuracy with the lowest roll-over and the highest perpendicularity of gear part. Experiment under the same conditions as FE-simulation for FRD was performed by mechanical press. External gear of recliner produced by mechanical press indicated similar dimensional accuracy with that produced by fine blanking press. Results of the performance test showed that the product manufactured by the developed process satisfied the required strength and durability. As a result, it is shown that gear forming by using FRD and conventional mechanical press is effective for high dimensional accuracy and productivity without fracture in gear part.

목차 (Table of Contents)

• 1. 서 론 1
• 1.1 연구 배경 1
• 1.2 연구 동향 3
• 1.3 연구 목적 및 범위 5
• 2. 자동차 시트 리클라이너의 정밀 전단가공 기술 7
• 2.1 정밀 전단가공 기술 7
• 2.1.1 파인블랭킹 7
• 2.1.2 유동제어성형 9
• 2.1.3 파인홀드스탬핑 10
• 2.2 자동차 시트 리클라이너 구조 및 제조 방법 11
• 3. 기계식 프레스에 의한 리클라이너의 제조공정 개발 12
• 3.1 리클라이너 기어성형 공정설계 12
• 3.2 기어성형 공정의 유한요소 모델링 15
• 3.2.1 연성파괴기준 16
• 3.2.2 성형성 평가 기준 17
• 3.3 기어성형 공정 해석 결과 및 고찰 18
• 3.4 금형 제작 및 실험 22
• 4. 리클라이너의 성능 평가 및 결과 23
• 4.1 치수정밀도 평가 23
• 4.2 성능 평가 24
• 4.2.1 작동력 시험 24
• 4.2.2 정하중 시험 24
• 4.2.3 내구성 시험 25
• 5. 결 론 27
• References 29
• Tables 33
• Figures 35
• Abstract 66