http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
헬리컬 기어 치수정밀도 향상을 위한 전방압출 공정설계에 관한 연구
정택우(T. W. Jung),이영선(Y. S. Lee),문영훈(Y. H. Moon),이일환(I. H. Lee),최석탁(S. T. Choi),강성훈(S. H. Kang) 한국소성가공학회 2010 한국소성가공학회 학술대회 논문집 Vol.2010 No.5
This work was focused on improvement of the filling degree of the material within the die during forward extrusion of helical gear. For this, the effects of billet, punch and mandrel shapes on the materials flow during helical gear forging were investigated using finite element simulations. In the work of literature, the helical gear was produced by forward extrusion with combined spur and helical gear dies using the tube-shape material. However, simulation results showed that the material was not completely filled within the die and the resultant dimensional error between the die and forged helical gear is very high. In order to reduce the error between the two, forward extrusion process of helical gear with tapered mandrel was proposed. It was found from simulation results that the dimensional error is dramatically decreased in case that tapered mandrel is used in forward extrusion of helical gear.
배압성형을 이용한 냉간단조 헬리컬 기어의 치수정밀도 향상에 관한 연구
김홍석(H. S. Kim),정현철(H. C. Jung),이영선(Y. S. Lee),강성훈(S. H. Kang),이일환(I. H. Lee),최석탁(S. T. Choi) 한국소성가공학회 2009 한국소성가공학회 학술대회 논문집 Vol.2009 No.5
As important mechanical elements, gears, gears have been several researches trying to make gear parts with cold or warm forging in order to reduce cost and time required to gear manufacturing process. Although forging processes of spur and bevel gears have been developed as practical level owing to active previous researches in Korea, the manufacturing of helical gear has been still depended on traditional gear cutting processes such as hobbing, deburring and shaving. In order to manufacture helical gears with cold forging process, a research project supported by government has been conducted by Daegu university, KIMS and TAK and this paper deals with effects of back pressure forming technique to cold forging of helical gear as a fundamental research.
냉간 단조용 금형 수명 및 단조품 품질 향상을 위한 금형 특성 연구
이영선(Y.S. Lee),권용남(Y.N. Kwon),권용철(Y.C. Kwon),이정환(J.H. Lee),최석탁(S.T. Choi) 한국정밀공학회 2006 한국정밀공학회 학술발표대회 논문집 Vol.2006 No.5월
The characteristics of the tool system give many effects into the costs and qualities for the finished components. Therefore, a tool life is one of the important issues on cold forging industry. However, since variables related with tool life are many complicated, the studies for solution should be investigated by the systematic research approach. In this study, heat-treatment of tool material is investigated to improve the tool life. Deep cryogenic treatment of tool steel is very efficient to improve the wear resistance due to the fine carbide. And, it is investigated that the shape and dimension of tool give effect into both tool life and quality of forged product.
김홍석(H. S. Kim),김낙현(N. H. Kim),이일환(I. H. Lee),최석탁(S. T. Choi),이영선(Y. S. Lee) 한국소성가공학회 2010 한국소성가공학회 학술대회 논문집 Vol.2010 No.5
The importance and application of helical gears as crucial parts of automobiles have been increased steadily owing to its higher power transferring performance with reduced geometrical limitations compared to spur gears. However, the traditional gear manufacturing methods such as hobbing and deburring require long processing time and expensive machines so that there have been intensive efforts trying to make gears by using forging process. Although forging processes for spur and bevel type gears have been developed as practical level, the manufacturing of helical gears has been still depended on traditional cutting process. Therefore, this paper seeks to develop a cold forging process for a helical gear with the helix angle of 18.4225° and the pitch diameter of 43.4571 ㎜. A cold extrusion process was applied due to the relatively small diameter of the target part and the material deforming behaviors according to die geometries were considered by using CAE analysis. Finally, extrusion experiments were conducted and it was found that the helical gear can be manufactured by the cold extrusion process.