• 제목/요약/키워드: 유공압

검색결과 919건 처리시간 0.026초

고속 공기압 실린더 내장용 쿠션기구의 특성 비교 (Characteristic Comparison on Internal Cushion Devices at High-speed Pneumatic Cylinders)

  • 김도태;장중걸
    • 한국자동차공학회논문집
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    • 제21권6호
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    • pp.24-30
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    • 2013
  • This paper studies the comparative analysis on two different internal cushion devices (the types of needle and relief valve) used to absorb the energy which is generated when the pneumatic cylinder moves with the load at meter-out speed control system. The effect at varying the piston velocity under same driving condition is mainly investigated. The simulation results on pressure in the cushion chamber and the dynamic behavior of the relief valve type cushion device are compared with the needle valve type. Design and performance are improved with the cushion configuration of better quality at high-speed pneumatic cylinder. Based on the relation between absorbed energy and impact energy at cushion process, cushion performance at pneumatic cylinder is evaluated.

고속 공기압 실린더용 릴리프밸브형 쿠션기구의 특성 해석 (Analysis of Cushion Mechanism with Relief Valve for High-Speed Pneumatic Cylinders)

  • 김도태;장중걸
    • 한국자동차공학회논문집
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    • 제18권3호
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    • pp.95-103
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    • 2010
  • This paper presents a simulation model of a double-acting high-speed pneumatic cylinder with a relief valve type cushion mechanism. The model predicts piston motion, mass flow rate, pressure and temperature time histories of cushion chamber. Of interest here is to investigate the cushioning effect of varying the piston and piston-rod diameter, cushion ring diameter and length, and stoke in cushion mechanism. As a result, this cushion mechanism is found to be adequate under high-speed driving of pneumatic cylinders. The simulation model proposed here will be very useful to analyze the dynamic characteristics and to improve or design the better cushion mechanism in high-speed pneumatic cushion cylinders.

충격압력을 이용한 고압용 유압호스 조립체의 수명분석 (Life Analysis of High Pressure Hydraulic Hose Assemblies by Impulse Test)

  • 이용범;김형의;유영철;박종호;고재명
    • 유공압시스템학회논문집
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    • 제1권1호
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    • pp.10-16
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    • 2004
  • The failures such as leakage and burst stemmed from the repetitive motions of bending and stretching of the assembly of hydraulic hose in construction machines, agriculture machines, vehicles, and industrial heavy machines can induce big troubles. Therefore, the hydraulic hose itself eventually requires an estimation of life to operate the hydraulic system safely. In this research, we have qualitatively selected the efficient test items by the analysis of the life and potential failures of hydraulic hose. We have used more than seven of hydraulic hoses simultaneously for the research. We have applied impulse pressure and half omega flexing motions to the accelerated life testing Test results have been expressed by employing weibull plot.

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고전압 차단기용 솔레노이드 액추에이터의 거동 (Behavior of the Solenoid Actuator for High-Voltage Circuit Breaker)

  • 윤소남;함영복;안병규;김고도
    • 유공압시스템학회논문집
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    • 제1권3호
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    • pp.1-6
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    • 2004
  • In the last few years, a considerable number of studies have been made on On-Off solenoid for fluid control. But, only few attempts have so far been made at solenoid actuator for high-voltage circuit breaker. In case of the high-pressure and high-flow system like high-voltage circuit breaker, a big size of On/Off solenoid is necessary which size is proportional to control pressure and flow rate. So, it is non-effective in the view point of system optimization. In this paper, On/Off solenoid actuator with the farce amplifier connected to the solenoid rod was proposed to get a high mechanical force and a fast response time. The magnetic force and the mechanical stress distributions were analysed using finite element analysis. The performances of suggested solenoid actuator were evaluated through the experimental results and compared with the analysis results.

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공압실린더의 누설유량 계측방법에 관한 연구 (A Study on the Measurement Method of Leakage Flow-rate for Pneumatic Cylinder)

  • 장지성;지상원;정지현;강보식
    • 유공압시스템학회논문집
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    • 제3권1호
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    • pp.15-19
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    • 2006
  • In this study, a measurement method of leakage flow-rate for pneumatic driving apparatus is proposed. The existing measurement methods of leakage flow-rate of air need disassemble the test component. Therefore, there is no effective method to measure the leakage flow-rate while operating pneumatic driving apparatus. In this study, the leakage flow-rate is measure from the pressure change in an isothermal chamber that can realize isothermal conditions by stuffing steel wool into it. Therefore, wide range of flow-rate could be measured only from the pressure response and the leakage flow-rate can be measured during operating pneumatic driving apparatus. The effectiveness of the proposed method is proved by experimental results.

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