• 제목/요약/키워드: 진동 테이블

검색결과 48건 처리시간 0.027초

2차원 고주파 진동을 이용한 미세 밀링가공 (Micro Milling using High Frequency 2-dimensional Vibration)

  • 김기대
    • 한국기계가공학회지
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    • 제9권6호
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    • pp.66-70
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    • 2010
  • Using two piezoelectric materials orthogonally arranged, 2-dimensional(2D) vibration in a excitation workpiece table was generated. In this study, micro milling using high frequency 2D vibration was proposed, whose locus of cutting tool is combined with original trochoid locus of milling tool and 2D elliptical locus of excitation table. From the cutting results of 2D vibrational micro milling of nickel alloy, it was observed that the machining quality and the roughness of machined surface were enhanced compared to conventional milling in a side cutting whose immersion ration is relatively low, whereas there was little betterment in a slot cutting.

미세밀링 가공 시 2차원 진동이 표면거칠기에 미치는 영향 (Effects of 2-dimensional vibration on the surface roughness in micro milling)

  • 김기대
    • 한국기계가공학회지
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    • 제12권4호
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    • pp.81-86
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    • 2013
  • For a 2-dimensional(2D) vibration milling, an excitation work-table was developed using two piezoelectric materials orthogonally arranged, where the trochoidal trajectory of a milling tool is combined with 2 dimensional elliptical vibration of a work-table. Applying 3kHz excitation frequency and 7~8mm amplitude of vibration to micro milling process with brass and nickel materials, the roughness in both bottom and side surface is much more improved compared to the surface by conventional milling process, which is attributed to decreased frictional force, increased cutting speed, and rubbing effect of a 2 dimensional vibration.

공기스프링을 이용한 방진테이블의 능동 제어 (Active Control of Vibration Isolation Table Using Air-spring)

  • 안채헌;임광혁;진경복;임경화
    • 한국소음진동공학회논문집
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    • 제17권7호
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    • pp.565-571
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    • 2007
  • In the process of accurate manufacture and measurement, it is necessarily required to isolate external or internal vibration due to external disturbance and internal actuators. The higher vibration isolation system gets damping around resonance, the better it is generally. This paper analyzes the performance of an existing passive air-spring for vibration isolation table by using experiment and simulation. Optimal design for a passive air spring can be obtained by tuning the size of the orifice. Also design for an active isolation system is carried out by applying PID controller and considering non-linearity of pneumatic characteristics with help of look-up table. We have developed the active vibration isolation table with the better isolation performance.

양방향 평면진동을 이용한 미세구멍가공 (Micro Drilling using 2-directional Vibration in a Plane)

  • 김기대
    • 한국기계가공학회지
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    • 제9권4호
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    • pp.38-43
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    • 2010
  • By generating 2-directional vibration in a xy plane of workpiece table, a newly developed micro drilling using 2-directional vibration was carried out. The vibration was produced by applying sinusoidal voltages to the orthogonally arranged piezoelectric materials built in the workpiece excitation table. Through the micro-drilling experiments using poly-carbonate and brass material, it was found that micro drilling using 2-directional vibration in a workpiece table could be an efficient method to enhance the form accuracy of machined workpiece by suppressing burr formation at both entry and exit region. A higher form accuracy could be obtained by increasing stiffness of feeding mechanism, decrease of geometric tolerance of combining jig, and development of high performance excitation table which generates amplified vibration at higher frequency.

정밀 제진대 개발 및 동특성에 관한 실험적 연구 (Development of precision vibration isolation table and study of dynamic characteristics with experiment)

  • 김인수;김종연;한문성;김영중
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 I
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    • pp.329-334
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    • 2001
  • Recently, the high precision technology can not be developed continuously if we don't have anti vibration technology. Vibration isolation technology using an air spring and laminated robber bearing is widely used because it has excellent vibration isolation characteristics. We developed high precision vibration table with two good element(air spring and LRB) for semiconductor factory. Air Spring is used for isolating the vertical vibration and LRB is used for isolating the horizontal Vibration. As a result, It has D-Class degree in BBR-Criteria. In this paper, we talk about orifice characteristics in the self-damped air spring and design flow of the laminated robber bearing. The orifice characteristics is delicate shade of length and diameter. When we do experimentation to find orifice characteristics, length is fixed and diameter is changed. The orifice diameter is the wider and the air spring stiffness is the softer.

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공기스프링을 이용한 방진 테이블의 능동 제어 (Active Control of Vibration Isolation Table Using Air-spring)

  • 안채헌;임광혁;권혁진;정진훈;배윤화;진경복;임경화
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.831-836
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    • 2006
  • In the process of accurate manufacture and measurement, it is necessarily required to isolate external or internal vibration due to external disturbance and internal actuators. The higher vibration isolation system gets damping around resonance, the better it is generally. This paper analyzes the performance of an existing passive air-spring for vibration isolation table by using experiment and simulation. Optimal design for a passive air spring can be obtained by tuning the size of the orifice. Also design for an active isolation system is carried out by applying PID controller and considering non-linearity of pneumatic characteristics with help of look-up table. We have developed the active vibration isolation table with the better isolation performance.

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정밀기기가 탑재된 방진대의 주파수성형 슬라이딩모드 제어 (Frequency-shaped Sliding Mode Control of Isolation Table Equipped with Precision devices)

  • 김효준;박영필
    • 한국소음진동공학회논문집
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    • 제12권2호
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    • pp.124-131
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    • 2002
  • This paper presents the design of an active vibration suppression controller for an air-spring type vibration isolation table. Firstly, isolation system model is constructed considering the isolation table, attached equipment and voice-coil actuator. An active control system is designed based on frequency-shaped sliding mode control theory rewarding high frequency uncertainties with respect to attached equipments on the isolation table. Finally. the performance of the active isolation system is evaluated by simulation under some disturbance conditions which are transmitted from base structure of the isolation system.

주파수 보정법에 의한 구동기 외란 파라미터 정밀 결정 (PRECISION IDENTIFICATION OF ACTUATOR DISTURBANCE PARAMETER BY FREQUENCY COMPENSATION)

  • 이현호;전동익;오화석
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2005년도 한국우주과학회보 제14권1호
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    • pp.138-142
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    • 2005
  • 위성자세제어용 구동기 인 반작용 휠은 축 방향 토크뿐만 아니 라 횡 축 방향 외 란 토크와 힘을 발생시켜 위성의 정밀 지향 안정성에 영향을 미치게 된다. 이를 위해서는 반작용 휠 구동시의 발생 외란을 정밀하게 측정할 필요가 있다. 그러나 반작용 휠의 구동은 측정테이블의 진동을 야기 시키고 테이블의 공진 주파수 영역에서 큰 측정 오차를 유발한다. 본 논문은 이러한 진동오차들을 줄이기 위하여 주파수 보정법에 의한 사후처리 과정을 제시하고, 이 보정법으로 얻어진 데이터들로부터 외란 파라미터를 결정함으로써 구동기 외란의 보다 정밀한 측정을 가능케 하기 위함이다. 이 보정법을 적용함으로써 구동기 외란 측정 주파수범위를 넓힐 수 있다.

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고속 정면밀링가공을 위한 진동 파라미터에 관한 연구 (A Study on the Vibration Parameters for High Speed Face Milling Machining)

  • 장성민;이승일
    • 한국산학기술학회논문지
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    • 제14권9호
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    • pp.4149-4155
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    • 2013
  • 더 빠른 절삭속도와 이송속도를 위한 고속가공은 표면품위와 재료제거율의 증가를 초래한다. 이 논문은 고속가공을 위한 정면밀링커터를 사용한 가공에서 획득된 진동특성에 관한 절삭조건의 영향을 연구하였다. 이 논문에서, 직교배열 테이블에 기초한 다구찌 실험계획법은 고속 정면밀링커터를 사용한 진동특성을 연구하기 위해 적용되었다. 실험조건은 직교배열 $L_{27}(3^{13})$ 을 사용하였다. 실험의 계획과 분석은 S/N비(신호 대 잡음비)와 분산분석을 이용하여 진동에 관한 절삭조건의 영향을 연구하기 위해 수행되었다. 절삭 파라미터 즉 이송속도, 챔퍼길이, 절삭속도 그리고 절삭깊이는 진동 특성치를 고려하여 최적화 되었다.

공기스프링의 최적설계 및 방진 테이블의 능동 제어 (Optimal Design of Air-spring and Active Control of Vibration Isolation Table)

  • 안채헌;김호성;임광혁;진경복;임경화
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.909-914
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    • 2006
  • Vibration isolation tables are mostly required in precise measurement and manufacturing system. Among the vibration isolation tables, an air spring is the most favorable equipment because of low resonant frequency and high damping ratio. However, it is difficult to design the air spring with the required stiffness and damping ratio. Futhermore, whenever conventional active control methods are applied to the air spring, it may be difficult to obtain effective control performance due to high nonlinearity of air spring. In this paper, the optimal design of the air spring is performed using genetic algorithm to bring out low resonant frequency and high damping ratio. Also, active control of the vibration isolation table with 3-DOF model is proposed using the adaptive control method. Through experiments, optimal design is shown to be effective. And performance of the proposed control method is verified to be better than those of the passive control method and the conventional active control methods.

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