• 제목/요약/키워드: Selection of Bearing Position

검색결과 8건 처리시간 0.018초

피봇식 패드 추력베어링의 성능 비교 (Comparison of the Performance of Pivoted Pad Thrust Bearings)

  • 김종수
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제22권3호
    • /
    • pp.337-342
    • /
    • 1998
  • In this paper the lubrication performances of line pivoted pad thrust bearing and point pivoted pad thrust bearing are studied by a numerical analysis. The running characteristic parameters such as nondimensional load carrying capacity nondimensional friciton power loss nondimensional flow rate and film thickness ratios are calculated for various circumferential pivot positions. The results provide a usdful data for the selection of pivot position in a pivoted and thrust bearing.

  • PDF

40,000rpm 고속 주축의 정·동특성 향상을 위한 베어링 위치 선정 (Selection of Bearing Position for Improving Static and Dynamic Stiffness of 40,000rpm High-speed Spindle)

  • 임정숙;정원지;이춘만
    • 한국기계가공학회지
    • /
    • 제8권1호
    • /
    • pp.10-17
    • /
    • 2009
  • Spindle design is very important for the improvement of the competitive power in production cost of high quality machine tools. The important factor in spindle design is not only to improve the natural frequency of spindle but also to reduce displacement of spindle end. In this paper, parameters those influence on static and dynamic stiffness of high-speed spindle have selected form preceding studies. And those selected parameters are applied to Taguchi Method. To perform FEM analysis, bearing conditions are selected with optimized condition. To know how to improve static and dynamic stiffness of machine tool spindle, natural frequency and displacement of spindle end are obtained by FEM analysis. The Taguchi Method was used to draw optimized condition of bearing position and it's stiffness. From these results, amplitude of vibration is enough good less than $3{\mu}m$ pk-pk of the spindle of 40,000rpm manufactured in this work by the optimal design.

  • PDF

주축 상태 모니터링 용 광파이버 변위센서 제작 및 성능평가 (Fabrication and Performances Tests of the Optical Fiber Position Sensor for Application to Spindle State Monitoring)

  • 신우철;홍준희;박찬규
    • 한국공작기계학회논문집
    • /
    • 제14권6호
    • /
    • pp.37-44
    • /
    • 2005
  • This paper presents fabrication techniques of the optical fiber position sensor (or spindle state monitoring. These include selection of components such as optical fibers, a laser-diode, a photo-diode, and op-amp IC of the signal process circuit. We also describe electric runout problem. The fabricated sensor has a linearity of $1.7\%$ FSO in the air gap range $0.1\~0.6mm$, a resolution of $0.37{\mu}m$ and a bandwidth of 6.3kHz. Finally, we have successfully operated a magnetic bearing spindle system using the sensors.

다공질 정압공기 베어링을 이용한 직진 테이블에 있어 주위환경이 움직임 정밀.정확도에 미치는 영향 (Influence of the environments on the movement precision of the guide table using externally pressurized porous air bearing)

  • 한응교;허석환;노병옥
    • 대한기계학회논문집
    • /
    • 제12권4호
    • /
    • pp.721-729
    • /
    • 1988
  • 본 연구에서는 직진테이블 시작품을 통해 주위환경에 의한 영향 중 주위온도 에 따른 움직임 정밀 정확도의 변화 및 지지조건이 움직임 정밀.정확도에 미치는 영향 에 대해 실험 연구하였다.

탐지확률 분석에 의한 입수점 선정 알고리듬 개발 방안 (A Development Method for Water Entry Point Selection Algorithm by Detection Probability Analysis)

  • 조성봉
    • 한국군사과학기술학회지
    • /
    • 제10권4호
    • /
    • pp.30-37
    • /
    • 2007
  • In this paper, Water Entry Point Selection Algorithm(WEPSA) for selecting an optimal Water Entry Point of anti-submarine missiles which maximizes Detection Probability about a given target was investigated. WEPSA is a method which decides the position of an optimal Water Entry Point with calculating the target Detection Probability of a torpedo in the whole domain which centered by the target, performing the Monte-Carlo Simulations which include errors for the target informations and for weapon delivery. We can decide an optimal Water Entry Point of anti-submarine missiles which maximizes Detection Probability about a given target with WEPSA, if we get target informations about target range, target bearing, target speed and target course from Combat Systems.

자기 베어링 주축시스템의 유도형 센서 개발 (Development of Inductive Sensor in Magnetic Bearing Spindle System)

  • 신우철;이동주;홍준희;노명규
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
    • /
    • pp.32-37
    • /
    • 2000
  • In a high speed spindle system, it is very important to monitor the operation of the spindle to prevent catastrophic damage to the system. Widely used sensors for monitoring are eddy-current and capacitive types. These sensors provide high accuracy of monitoring, but their steep prices lead to expensive high speed spindle system. The main god of our research is to develop technology to produce high speed spindle system utilizing magnetic bearings. As active magnetic bearings require position sensors for feedback control, a noncontact position sensor is bang developed as a part of this main goal. Once developed, it will contribute to affordable high speed spindle system. In this paper, we report the selection process of the sensor types and the experimental results with driving circuits.

  • PDF

원위경비골인대 손상의 치료 동향: 대한족부족관절학회 회원 설문조사 분석 (Current Trends in the Treatment of Syndesmotic Injury: Analysis of the Korean Foot and Ankle Society (KFAS) Member Survey)

  • 조재호;조병기;정비오;정진화;배서영;2021 대한족부족관절학회
    • 대한족부족관절학회지
    • /
    • 제26권2호
    • /
    • pp.95-102
    • /
    • 2022
  • Purpose: This study was based on the Korean Foot and Ankle Society (KFAS) member survey and aimed to report the current trends in the management of syndesmotic injuries over the last few decades. Materials and Methods: A web-based questionnaire containing 36 questions was sent to all KFAS members in September 2021. The questions were mainly related to the preferred techniques and clinical experiences in the treatment of patients with syndesmotic injuries. Answers with a prevalence ≥50% of respondents were considered a tendency. Results: Seventy-six (13.8%) of the 550 members responded to the survey. The results showed that the most preferred method to diagnose a syndesmotic injury was magnetic resonance imaging (MRI). Intraoperatively, the external rotation stress test and the Cotton test were most frequently used to confirm syndesmotic diastasis. The reduction was usually done by a reduction clamp. One 3.5-mm screw was used most frequently over three cortices at 2~4 cm above the ankle joint. The preferred ankle position during fixation was 0° dorsiflexion. Removal of the syndesmotic screw was routinely done by most surgeons, mainly because of the limitation of movement and risk of screw breakage. Factors that affect suture button selection included non-rigid fixation which enables adequate fixation, early weight-bearing, and an infrequent need to remove the hardware. Inadequate reduction was considered the main factor that affects poor prognosis. Conclusion: This study proposes updated information about the current trends in the management of syndesmotic injuries in Korea. Consensuses in both the diagnostic and therapeutic approach to patients with syndesmotic injury were identified in this survey study. This study may raise the awareness of the various possible approaches toward the injury and should be used to further establish a standard protocol for the management of syndesmotic injuries.