• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.515-518
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• 2002

콘트롤밸브는 지역 냉${\cdot}$난방 및 APT, 대형 빌딩의 냉온수, 중온수 및 공조배관 시스템에 사용되어 유체적 바란스를 이루는데 사용된다. 이와같이 유체의 흐름을 조절하기 위하여 사용되는 콘트롤 밸브가 때로는 소음 문제를 일으키기도 한다. 최근 들어 밸브의 소음이 문제가 되는 경우가 빈번해 지고 있다. 밸브의 기본적 기능을 충족시키기 위해서는 영구적인 수두 손실이 필요하며 이러한 수두손실을 발생시키는 과정에서 유체 흐름에 의해 발생한 난류가 커다란 밸브 소음을 유발하게 된다. 본 연구에서는 콘트롤 밸브 소음 특성 평가 방법을 검토하였다. 밸브 및 배관으로 이루어진 시스템에서 발생되는 소음을 예측하는 절차를 살펴보았다. 밸브의 음향 파워레벨을 측정하고 유량 및 차압의 변화에 따른 소음 예측식을 결정 하였다. 본 연구에서 제시한 밸브 소음 측정 방법은 새로운 밸브의 소음특성 평가, 밸브 소음의 예측 그리고 서로 다른 밸브 사이의 성능비교 등에 사용될 수 있을 것이다.

• The Journal of the Acoustical Society of Korea
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• v.21 no.8
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• pp.703-707
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• 2002

This paper proposes new method for predicting sound power emitted from the control valve and piping system. The sound power level measurement method using the reverberation chamber is much easy to apply in the field compared to the method using the anechoic chamber. Measured sound power was used to determine the coefficients of the equation predicting sound power level. The noise prediction equation was developed at relative flow coefficient, 0.11. The sound power level predicted is in good agreement with the measured value. Proposed method can be used to express the noise characteristics of the control valves.

• Journal of Energy Engineering
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• v.22 no.4
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• pp.394-398
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• 2013

At present, using of electromagnetic control valve (ECV) in external variable displacement swash plate type compressor is a common issue. Solenoid operated ECV controls vehicle air conditioning system through a pulse width modulation (PWM) input signal that supplied from an external source. Different port pressure controls the swash plate movement inside the compressor at certain angles that finally determines the refrigerant flow rate to the vehicle compartment for passengers comfort. In this paper, crankcase pressure flow (Pc flow) is calculated with some ECV samples with corresponding to amount of variable supply of current ranges from 0.20Amp to 0.95Amp.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.203-203
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• 2004

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.167-174
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• 1997

In this paper, the mathematical model of the hydraulic control valve is formulated, that is, this dynamic modeling which includes the motion equations and continuity equations can analyze the dynamic characteristics of the hydraulic control valve. The control valve for the transmission has the Over Speed Protection to protect a hydraulic travel motor. Therefore, this simulation shows the over speed protection and researches the main design parameters. The results of the computer simulation were assured through the experiment. From the comparison between both results, it is shown that this simulation program is useful and effective.

• Journal of the Korean Magnetics Society
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• v.7 no.6
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• pp.321-326
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• 1997

We analyzed an important part of control valve, magnet unit, which is used to control the fluid. Magnetic circuit which is composed of magnet and yoke is analyzed using finite element method. Then, flux density and coil force were calculated and compared with those of measured. According to the simulation results, the gap field, force constant, and permeance coefficient were 3~5 kG, 27.5 N/A, 22.1, respectively, which corresponded reasonably well with the measured values. We also obtained reluctance factor of 1.1 and fringing factor of 1.4 by simulation.

• Proceedings of the Korean Magnestics Society Conference
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• 1995.05a
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• pp.28-29
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• 1995

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1993.04a
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• pp.108-111
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• 1993

일반적으로 정수압 베어링은 저진동, 저마찰 및 높은 댐핑 특성을 가지며 하중 지지 용량도 커서 공작 기계, 측정 기구등에 광범위하게 하용된다. 특히 여러 산업이 발달함에 따라 점차 정밀 부품의 필요성이 증가되고 있고 공작 기계의 용량도 점차 대형화되는 추세에 있다. 이에 따라 공작 기계의 미끄럼 운동을 지지하는 베어링은 높은 강성 및 높은 하중 지지용량을 갖게할 필요가 있다. 본 논문에서는 능동적 급유 방식의 리스트릭터의 한 종류인 다이아프램 제어 밸브 (diaphram control valve)와 수동적 급유 방식의 리스트릭터의 한종류인 오리프스의 특성을 이론적으로 해석하고 실험을 통하여 이론 해석의 타당성을 검증하고 결과를 도시하고자 한다.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.214-221
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• 1999

In this research, a power-assisted steering system is modeled as a part of a full vehicle dynamic model. The dynamic model of the steering system incorporates hydraulic and dynamic relations between major parts of a steering system, such as steering column, control valve, rack and pinion gear. Through an experimental setup of the steering system, the steering system model is validated. The steering model is included in a full vehicle dynamic model of a car, where kinematic relations between steering and suspension system are defined, and various simulations are performed to evaluate the performance of steering system in conjunction with overall dynamic performance of the vehicle.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1755-1759
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• 2003

The hydraulic excavator has been a popular research object for automation because of its multi-workings and economic efficiency. The objective of this paper is to design each components and to construct boom, arm, bucket circuit. These models modeled with AMESim show us change of variables and behavior of excavator. Simulation model will be used for simulator of excavator.