• Title/Summary/Keyword: Twin cam

검색결과 4건 처리시간 0.021초

휴대폰 폴더힌지기구를 위한 원통캠 형상 설계에 관한 연구 (A Study on the Shape Design of Cylindrical Cam in a Folder Hinge Mechanism for Mobile Phones)

  • 이수준;박종근
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.1613-1616
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    • 2005
  • In this paper, we developed an algorithm of generating cam contour curve for hinge mechanism of folder-type mobile phone. The main feature of this hinge mechanism is that we can operate uniform torque to open or close the mobile phone. We divided the opening or closing intervals of the cam into finite sub-intervals, and then we determined the cam contour curve of each sub-interval as a parabolic curve. Finally, these finite parabolic curves form the total cam contour. We can design single cam, which composed moving cam with contour curve and fixed cam that plays only roller, and twin cam with contour curve that is made up the pair of two cams symmetrically.

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Machining Center의 고속 ATC 제어 시스템의 개발 (Development of Control System of High-speed ATC of Machining Center)

  • 한동창;이동일;송용태;이석규
    • 한국정밀공학회지
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    • 제19권9호
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    • pp.125-132
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    • 2002
  • We use a compound-cam twin arm structure and random tool access method to achieve a faster ATC (Automatic Tool Changer) system for the accurate position and rotation control of a tool magazine and an exchange am. Based on the data obtained from various sensors, it is possible to follow the sequence of commands in each control step for an exchange arm. However, it is not so easy to reduce the exchange time of the system because of the slow responses of the sensors and execution mode delays of PLC (Programmable Logic Controller) scan time. In this paper, we propose a new programmed limit-switch position control method to obtain the shortest possible delays for the random tool access method and compound-cam twin arm structure. With some experimental results, we have achieved below 0.9sec tool exchange time with the proposed method.

상하악 전치부 심한 변색과 마모를 보이는 쉐그렌 증후군 환자에서 twin-stage법을 이용한 수복증례 (Rehabilitation using twin-stage method for a Sjögren's syndrome patient with severe discoloration and attrition on upper and lower anterior teeth)

  • 이선기;양홍서;박상원;임현필;윤귀덕
    • 대한치과보철학회지
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    • 제54권3호
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    • pp.291-297
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    • 2016
  • 쉐그렌 증후군($Sj{\ddot{o}}gren^{\prime}s$ syndrome)을 가진 환자들은 구강건조증으로 인하여 치질이 연화되어 마모와 변색을 가지는 경우가 빈번하다. 전치부가 심하게 마모된 경우 전방유도의 상실 및 교합의 부조화, 보철수복을 위한 공간의 부족 등의 문제가 발생할 수 있는데, twin-stage method를 이용하여 수복시 전방유도와 측방유도를 통해 구치부 이개량을 확보하여 중심위와 편심위에서 모두 이상적인 교합을 형성할 수 있다. 본 증례는 쉐그렌 증후군으로 인하여 상, 하악 전치부의 심한 변색과 마모를 가진 환자에게 twin-stage method를 이용하여, 수복하였기에 보고하는 바이다.

이중진공관형 태양열 집열기의 하절기 과열 방지에 대한 연구 (A study on reducing temperature rise of twin-glass evacuated tube solar collector during summer time)

  • 배상은;배철호;남현규;신기열;유인호
    • 한국태양에너지학회 논문집
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    • 제33권3호
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    • pp.36-41
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    • 2013
  • The reflection plate in twin-glass evacuated tube solar collector is controlled to reduce the overheat during the summer time. The sliding type and folding types are suggested and tested. The sliding type changes the plate angle and the folding type changes the opening angle of the reflection plate. By scattering the focus of the reflected radiation from the reflection plate, the temperature rise of the working fluid can be reduced. The sliding type shows the best results in overheat reduction. When solar radiation is 900 $W/m^2$, the temperature rise in one sliding type collector is reduced about $2^{\circ}C$ compared to that of the normal solar collector. When this method is applied to seven series-collectors in the field, the reduction of temperature rise during the summer time should be significant.