• 제목/요약/키워드: Hydrostatic Spindle Optimization

검색결과 6건 처리시간 0.016초

연삭기용 유정압베어링주축의 최적화에 관한 연구 (The Optimization of a Hydrostatic Spindle System for Grinding Machines)

  • Lee, C.H.;Park, C.H.;Lee, H.S.
    • 한국정밀공학회지
    • /
    • 제13권7호
    • /
    • pp.140-147
    • /
    • 1996
  • Machining accuracy of machine tools spindles using the hydrostatic bearing, largely depends on the static stiffness and the thermal deformation of the spindle unit. In this paper, the modelling and static, thermal analysis of the hydrostatic spindles were performed for the relationship between the design variables like the bearing span, overhang, bearing stiffness and static stiffness at spindle. The goal of optimization is the mazimum, static stiffness at spindle nose with lower temperature rise in hydrostatic bearing. Temperature rise of hydrostatic bearing is minimized with the variables of spindle diameter and oil supply pressure. Finally, validity of the proposed algorithm is verified by improving the static, thermal performance of the existing hydrostatic spindles.

  • PDF

크랭크 샤프트 연삭기용 유정압 스핀들의 유막 간격 선정에 관한 연구 (A Study on the Determination of the Oil Gap in the Hydrostatic Spindle System for a Crank Shaft Grinding Machine)

  • 박동근;최치혁;이인재;이춘만
    • 한국정밀공학회지
    • /
    • 제28권4호
    • /
    • pp.410-415
    • /
    • 2011
  • A cylindrical type of self-controlled restrictor is designed for hydrostatic bearing of crank shaft for a grinding wheel spindle. The effect of operation parameters, clearance between spindle and housing on bearing stiffness are analyzed to determine the optimum conditions of operation parameters. The lowest values of the supply pressure and the loads by the theoretical and experimental results assuming oil film thickness and shape of pocket are compared.

대형 선박엔진 크랭크샤프트 가공용 복합가공기 기술 개발 (Development of a Multi-Tasking Machine Tool for Machining Large Scale Marine Engine Crankshafts and Its Design Technologies)

  • 안호상;조용주;최영휴;이득우
    • 한국정밀공학회지
    • /
    • 제29권2호
    • /
    • pp.139-146
    • /
    • 2012
  • A multi-tasking machine tool for large scale marine engine crankshafts has been developed together with design technologies for its special devices. Since work pieces, that is, crankshafts to be machined are big and heavy; weight of over 100 tons, length of 10 m long, and diameter of over 3.5 m, several special purpose core devices are necessarily developed such as PTD (Pin Turning Device) for machining eccentric pin parts, face place and steady rest for chucking and resting heavy work pieces. PTD is a unique special purpose device of open-and-close ring typed structure equipped with revolving ring spindle for machining eccentric pins apart from journal. In order to achieve high rigidity of the machine tool, structural design optimization using TMSA (Taguch Method based Sequential Algorithm) has been completed with FEM structural analysis, and a hydrostatic bearing system for the PTD has been developed with theoretical hydrostatic analysis.

고정밀 대형 부품가공용 복합가공기 원천기술 개발 (Development of Core Technologies of Multi-tasking Machine Tools for Machining Highly Precision Large Parts)

  • 장성현;최영휴;김수태;안호상;최학봉;홍종승
    • 한국정밀공학회지
    • /
    • 제29권2호
    • /
    • pp.129-138
    • /
    • 2012
  • In this study, three types of large scale multi-tasking machine tools together with core technologies involved have been developed and introduced; a multi-tasking machine tool for large scale marine engine crankshafts, a multi-tasking vertical lathe for windmill parts, and a large scale 5-axis machine tool of gantry type. Several special purpose devices has been necessarily developed for the purpose of handling and machining big and heavy workpieces accurately, such as PTD (Pin Turning Device) with revolving ring spindle for machining eccentric crankshaft pins, hydrostatic rotary table and steady rest for supporting and resting heavy workpieces, and 2-axis automatic swiveling head for high-quality free surface machining. Core technologies have been also developed and adopted on their detail design stage; 1) structural design optimization with FEM structural analysis, 2) theoretical hydrostatic analysis for the PTD and rotary table bearings, 3) box-in-box type cross-rail and octagonal ram design to secure machine rigidity and accuracy, 4) constant spindle rpm control against gravitational torque due to unbalanced workpiece.

반응표면분석을 이용한 연삭가공용 스핀들 형상 최적화 (Shape Optimization of Grinding Spindle using Response Surface Analysis)

  • 배경태;김귀남;최부영;문홍만;노정필;허선철
    • 한국해양공학회지
    • /
    • 제29권1호
    • /
    • pp.56-61
    • /
    • 2015
  • To improve the accuracy of a machine, research needs to be conducted on the relationship between the output variables and design variables of a spindle-shaped part from the thermal and static viewpoints. Therefore, research was carried out by examining the correlation of each variable to find the optimum conditions. Moreover, DOE (design of experiments) was extensively used. The model used in this study was a grinding spindle to which a hydrostatic bearing was applied. This model was used in a preliminary analysis based on the experimental results of the previous studies. The influences of the output variables and design variables were compared through a main effect analysis. Generated response surfaces were applied to the Kriging model. To optimize the model, a screening method was selected. In comparison with the initial model, the deformation of the optimized model designed by DOE decreased by 4.1 μm, while the thermal deformation decreased by 1.2 μm. Therefore, it was efficient to design a spindle-shaped part through DOE to improve the accuracy of the machine.