• 제목/요약/키워드: Unbalancing Vibration

검색결과 5건 처리시간 0.031초

3차원 표면 연마기 시스템의 최적설계 (Optimum Design of 3-Dimensional Panel Surface Grinder System)

  • 이수훈
    • 한국생산제조학회지
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    • 제9권2호
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    • pp.52-58
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    • 2000
  • the quality of a TV is closely connected with the high quality surface of Braun tube. To get high quality surface an improved grinding system is needed. It has three main parts : the housing part of supporting frame the outershaft part rotat-ed by motor and the innershaft part having eccentricity from the rotation axis of the outershaft. the housing part and the outershaft part are connected by outerbearings, The outershaft part and the innershaft part are connected by innerbearings. Although the outershaft part is rotated at high-speed the innershaft part is not rotated by offset coupling. The high quality grinding surface can be obtained by this mechanism of panel surface grinder, Because the innershaft is unbalanced by eccentricity from rotation axis of outershaft the unbalancing vibration is resulted In this rotor system with high-speed rota-tion the unbalancing vibration makes the opertion unstable. In this research the transfer function is obtained bythe frequency response analysis of finite element model. The simu-lation result is proved by comparing with the experimental result measured by signal analyzer Then the results are corre-lated. in order to improve the design an optimization method is used instead of two-planes balancing method The parts of the 3-dimensional panel surface grinder satisfy the each constraint, The result shows that the design of the panel surface grinder can be optimized.

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3상 BLDC 전동기 구동을 위한 4-스위치 인버터의 DC-Link 전압 불평형 보상 (DC-Link Voltage Unbalancing Compensation of Four-Switch Inverter for Three-Phase BLDC Motor Drive)

  • 박상훈;윤용호;이병국;이수원;원충연
    • 전기학회논문지P
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    • 제58권4호
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    • pp.391-396
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    • 2009
  • In this paper, a control algorithm for DC-Link voltage unbalancing compensation of a four-switch inverter for a three-phase BLDC motor drive is proposed. Compared with a conventional six-switch inverter, the split source of the four-switch inverter can be obtained by splitting DC-link capacitor into two capacitors to drive the three phase BLDC motor. The voltages across each of two capacitors are not always equal in steady state because of the unbalance in the impedance of the DC-link capacitors $C_1$ and $C_2$ or the variable current flowed into the capacitor's neutral point in motor control. Despite the unbalance, if the BLDC motor may be run for a long time the voltage across one of the capacitors is more increased. So the unbalance in the capacitors voltages will be accelerated. As a result, The current ripple and torque ripple is increased due to the fluctuation of input current which flows into 3-phase BLDC motor. According to that, the vibration of motor will be increased and the whole system will be instable. This paper presents a control algorithm for DC-Link voltage unbalancing compensation. The sampling from the voltages across each of two capacitors is used to perform the voltage control of DC-Link by using the feedforward controller.

레이저 변위계를 이용한 고속 회전스핀들의 필드 발란싱 기법 (Field Balancing Process of High Speed Spindle Using Laser Displacer)

  • 임성현;박영일
    • 한국생산제조학회지
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    • 제26권1호
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    • pp.114-120
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    • 2017
  • In recent years, applications of high speed rotating bodies have diversified. It is necessary for a device rotating at high speed to be balanced to minimize vibration. It is necessary to reduce the unbalancing factor to evenly wind the yarn. In this study, we also attempted to devise a technique to minimize the unbalance that occurs while assembling the components of spindles and to simplify the balancing procedure in the field. To balance the spindle, the vibration of the rotating spindle was measured using a laser displacement meter. We also performed balancing using the influence coefficient method by considering the phase.

동력전달요소에 따른 유정압 주축의 회전정밀도에 관한 연구 (Effects of the Power Transmission Units on the Rotational Accuracy of A Hydrostatic Spindle)

  • Park, C.H.;Ryu, G.W.;Jung, Y.G.
    • 한국정밀공학회지
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    • 제12권2호
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    • pp.59-68
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    • 1995
  • In this study, the effects of the power transmission units on the rotational accuracy are investigated experimentally in a hydrostatic spindle. The effects of warm up time, unbalancing and the position of measuring sensor are pre-examined for the determination of measuring conditions. The misalignment of the power transmission units and the vibration excited by the fluctuation of belt are considered as the dominant parameters of error motion. The variation and scatter of run out at the range of 0 to 3,000rpm in rotational speed are appropriated for the camparison of availabilities of the transmission units to precision spin- dles.

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