• 한국진공학회:학술대회논문집
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• 한국진공학회 1995년도 제9회 학술발표회 논문개요집
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• pp.61-62
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• 1995

Seiko Seiki develops and munufactures magnetic Bearing type Turbomolecular Pumps (MB-TMP), Seiko shipped 14,000 MB-TMPs and holds the world's largest share in the MB-TMP field. It developed a new 300 (l/s) class turbomolecular pump.

• 반도체디스플레이기술학회지
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• 제1권1호
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• pp.41-45
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• 2002

In modem manufacturing, new applations and technologies demand smaller, and functional devices to replace large systems. As miniaturization becomes a necessity, many companies are interested in small pumps for use in creating ultra-high vacuum, but past efforts to develop such systems have failed due to problems with vibration, stress, heat and power consumption. This paper shows analysis-based design techniques for high vacuum turbomolecular pump by finite element analysis.

• Applied Science and Convergence Technology
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• 제25권6호
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• pp.120-123
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• 2016

The rotor of a turbomolecular drag pump is generally made of an aluminum alloy. Its surface finish is affected by various processes that the rotor itself undergoes during the manufacturing phase. The impact of different surface finishes on the pumping performances of a turbomolecular pump has been mainly investigated by Sawada et al [1]. The present work aims to broaden the previous bibliographic study to the drag stages of a turbomolecular pump by testing the impact of different surface finishes on the compression ratio of the pump. Experimental tests have been made focusing on two processes: the corundum sandblasting and the glass microspheres shot-peening. Both the processes flatten and/or physically remove EDM melted spheres; in particular, blasted surfaces obtained by glass shot-peening are generally smoother than surfaces obtained by corundum sandblasting. In order to characterize the surface texture left by such processes, preliminary surface roughness measurements have been made on the drag rotor disks of several pumps. The experimental tests conducted on both sandblasted and shot-peened rotors confirms previous results obtained on the turbo stages by Sawada et al. [1], showing that the average roughness of the surface has an impact on the compression ratio of the pump; in particular, an increment in the surface roughness causes a corresponding increment in the compression ratio of the pump and vice versa. For the tested pumps, the higher surface roughness gives a factor of increment of about 2 on the measured hydrogen maximum compression ratio of the pump.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 추계학술대회 논문집
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• pp.321-322
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• 2009

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.667-668
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• 2010

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.361-365
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• 2002

In this paper, a magnetic suspension system with inductive sensors fur a high vacuum turbomolecular pump(TMP) is discussed. The performance of designed inductive position sensor is evaluated by static and dynamic test, and the test results show sensitivity of about 6,000 V/m and dynamic bandwidth of 750 ㎐. The protype of magnetic suspension system is designed and constructed with 5-axis magnetic bearing, inductive sensor and BLDC internal motor. With DSP based digital PID control system, the prototype is examined its high damping ratio and stable operation up to 20,000 rpm of rotation.

• 한국초전도ㆍ저온공학회논문지
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• 제24권4호
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• pp.65-70
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• 2022

A vacuum system is designed for thermal insulation of a 10 ton/day class air liquefaction cold box for liquid air energy storage. The vacuum system is composed of a turbomolecular pump, a backing pump and vacuum piping for the vacuum pumps. The turbomolecular pump is in combination with the backing pump for pumping capacity. The vacuum piping is designed with system installation conditions, such as distance from the cold box, connections to vacuum pumps and installation space. The capacity of the vacuum pump combination, namely pumping speed, is determined by analysis of the vacuum system, and pump-down time to 1×10^-5 mbar is estimated. Vacuum piping conductance, system pumping speed and outgassing rate are calculated for the pump-down time with the ultimate pumping speed range of the vacuum pump combination of 1400 - 2300 l/s. Although the pump-down time gets shorter by larger capacity vacuum pumps, it mainly depends on target vacuum degree and outgassing rate in the cold box. The pump-down time is estimated as 3 - 6 hours appropriate for cold box operation for the pumping speed range. Considering the outgassing rate has uncertainty, the vacuum pump combination with pumping speed of 1900 l/s is chosen for the vacuum system, which is middle value of the pumping speed range.

• 설비공학논문집
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• 제8권2호
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• pp.219-229
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• 1996

In the free molecular flow range, the pumping performance of a turbomolecular pump has been predicted by calculation of the transmission probability employing the integral method and the test particle Monte-Carlo method. The velocities of molecules incident upon a moving blade are given by the random numbers, which are sampled from the Maxwell molecular velocity distribution function. The present results agree quantitatively with the previous known numerical results. For a multi-stage pump, the velocity profile of molecules between two blade rows is not Maxwell distribution. In this case, the Monte-Carlo method is employed to calculate the overall transmission probability for the entire set of blade rows. When the results of the approximate method combining the single stage solutions are compared with those of the Monte-Carlo method for the pump having six rows at C=0.6, the approximate method overestimates as much as 36% in the maximum compression ratio and 19% in the maximum pumping speed than does the Mote-Carlo method.

• 한국진공학회지
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• 제10권3호
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• pp.303-311
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• 2001

터보분자펌프와 복합분자펌프의 배기성능을 나타내는 가장 중요한 항목인 배기속도 및 최대압축비와 함께 극한성능을 나타내는 임계배압을 현재 마련되어 있는 KS규격(안)을 준용하여 측정했다. 두 펌프의 성능이 어떤 점에서 차이가 나는지 비교하고 성능평가 절차에 대해 몇 가지 개선점을 제시했다.

• 한국진공학회지
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• 제19권4호
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• pp.256-264
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• 2010

본 논문에서는 고진공용 터보분자펌프의 비접촉 고속회전을 위한 자기베어링 시스템의 디지털 제어시스템의 설계에 대하여 소개하였으며, 실례로 800 l/s급의 고진공 펌프에 대하여 축 유연모드의 후방향 위험속도를 넘는 최대 40,000 rpm까지의 회전실험 결과를 나타내었다. 제안된 제어시스템은 기본적으로 PID 기반의 직접궤환 제어기와 자이로스코픽 모멘트 효과를 제어하기 위한 교차궤환기, 유연모우드 감쇄를 위한 리드필터와 동기진동 저감을 위한 노치필터 등으로 구성되어 있으며, 이러한 제어기는 자기부상형 터보분자펌프 외에 고속 플라이휠과 같은 자기베어링에 적용될 수 있다.