• 제목/요약/키워드: 고속 주축

검색결과 154건 처리시간 0.023초

고속 연삭기 주축 시스템의 회전체 역학 해석 (Rotor Dynamics Analysis of a Spindle System for a High speed Grinding Machine)

  • 최영휴
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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    • pp.714-719
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    • 2000
  • This paper describes a transfer matrix approach to analyze the dynamics of a high sped flexible rotor system supported at 2 positions by five ceramic bearings. The rotor system is modelled as lumped parameters in which many factors are considered not only lumped inertia or mass, bending moment, shear force but also gyroscopic effect and unbalance. The equation of motion is derived in the transfer matrix form, from which the eigenvalues equation is also derived. The transfer natural frequencies and modes. The eigenvalues, eigenmodes, campbell diagram, whirling critical speed, whirling modes, and the response of unbalance are calculated and discussed.

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High-speed CNC Grinding Center구조의 동적거동 해석 (Dynamic Characteristic Analysis of CNC Grinding Center)

  • 박종권;노승국;성활경
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.648-652
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    • 1996
  • Grinding Center(GC)는 머시닝센터가 갖는 드릴링, 태핑 등의 절삭가공의 수행은 물론 주축의 고속화, 이송계의 고정밀화를 토대로 연삭숫돌의 절삭성 회복과 다듬질면의 거칠기를 확보하기 위한 기계로서 Dressing/Truing장치, 기상계측 장치, CNC기능을 구비하여 테이블과 공구간에 3차원의 상대운동을 시킴으로써 평면연삭, 내면연삭, 홈연삭, 캠연삭 등의 복잡한 형상의 연삭가공에 대해서도 공정을 집약화 할 수 있는 기계이다.(중략)

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고속 주축계의 자켓의 유량 변화에 따른 냉각 특성 (A Study on the Cooling Characteristics of Cooling-Jacket in High-Speed Spindle according to the Flow Rate)

  • 김태원;김수태;최대봉;김태형
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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    • pp.332-336
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    • 2000
  • Cooling characteristics of cooling jacket for spindle system with built-in motor are studied. For the analysis, three dimensional model for the cooling jacket is built by using finite volume method. The three dimensional model includes the estimation on the amount of heat generation of bearing and built-in motor and the thermal characteristic values such as heat flux on the boundary. Numerical results show that flow rate are important factors for cooling characteristics of cooling jacket.

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열전달을 고려한 고속 주축계의 열특성 해석에 관한 연구 (A Study on the Thermal Characteristics of the High Speed Spindle considering Heat Transfer)

  • 백경근;김수태;최대봉;김태형
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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    • pp.285-290
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    • 2000
  • Unsteady-state temperature distributions and thermal deformations in high speed spindle are studied. For the analysis, three dimensional model is built considering heat transfer characteristics such as natural and forced convection coefficients Temperature distributions and thermal deformations are analyzed by using the finite element method. Results of analysis are compared with the measured data.

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고속가공의 절삭 깊이에 따른 알루미늄 합금 7075의 표면 거칠기에 대한 연구 (A Study on Surface Roughness of Al alloy 7075 to Cutting depth in High-speed Machining)

  • 박은식
    • 한국기계가공학회지
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    • 제9권6호
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    • pp.29-35
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    • 2010
  • Recently the industry high-speed machining has been applied to the automotive, aircraft, electronics parts machining because the effect of cost savings, machining time reduction and productivity improvement. In this study recently the aircraft structural aluminum alloy 7075 used in cutting the ball end-mill on the surface roughness terms most affect the parameters of the spindle speed and feed rate on the surface roughness of the work-piece according to the cutting depth is to investigate. Cutting depth at 0.3 mm has the lowest surface roughness.

고속 내면 연삭기 주축용 원추형 자기베어링 설계 연구 (Study on Design of Cone-Shaped Magnetic Bearing Spindle System for High Speed Internal Grinding)

  • 노승국;경진호;박종권;최언돈;양승준;이재응;김남용;이동주
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.79-83
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    • 2001
  • A cone-shaped active magnetic bearing spindle system for high speed internal grinding is designed and tested. The cone-shaped AMB system consists of only 4 couples of magnet, it can be smaller and lighter than conventional radial-axial-type AMB system. In this paper, the cone-shaped electromagnets are designed by magnetic circuit theory, and de-coupled direct feedback PID controller is applied to control the coupled magnetic bearings. The designed cone-shaped AMB spindle system is built and constructed with a digital control system, and tested its stbility and dynamic performances. As the results of the tests, this spindle runs up to 40,000 rpm with about 5 ${\mu}{\textrm}{m}$ of runout, and the AMB system provides high damping ratio eliminating overshoot and resonance speed.

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주축증속기를 이용한 금형강의 고속절삭에 관한 연구 (A Study on the High-Speed Machining of Die/Mold Material Using a Spindle-Speeder)

  • 이용철;강명창;이득우;김정석
    • 한국정밀공학회지
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    • 제15권8호
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    • pp.81-87
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    • 1998
  • High-speed machining is one of the most effective technologies to improve productivity. Because of the high speed and high feedrate, high-speed machining can give great advantages for the machining of dies and molds. In this paper, high-speed machining for HP-4 die material was carried out with a coated tungsten carbide ball endmill. In the high-speed machining, the cutting force and surface roughness of workpiece show various characteristics in different cutting conditions. Especially, the surface roughness of the workpiece depends largely on pick feed and feed-per-revolution of the ball endmill. In the condition where pick feed and feed-per-revolution are equal, better surface roughness is measured. By obtaining good surface roughness at high speed, efficiency of machining can be increased.

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고속 머시닝센터의 주축계 진동특성과 가공성 평가 (Evaluation of vibration property and machinability of spindle system in high speed machining center)

  • 김전하;강명창;김정석;김기태
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.16-21
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    • 2002
  • The high speed machining center(HMC) has been widely applied to manufacture a die and trial product in many machine industry. Because the evaluation fer the HMC is not sufficiently performed and the efficient cutting conditions aren't selected, a great loss has been caused in the cost aspect. In this study, the need of preliminary running time and unstable spindle speed is presented from the analysis of acceleration in idling. The Machinability fur the TiAlN coated flat end mill and STD11( $H_{R}$C60) is evaluated from the trends of tool wear and cutting force according to cutting conditions and slenderness ratio and a low response of tool dynamometer in high speed is proved. The resonance spindle speed is identified through the tool wear and natural frequency test.t.

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16 극의 반경방향 전자석을 갖는 자기부상 주축계 연구 (A Study on the Magnetically Suspended Spindle with 16-pole Radial Magnets)

  • 박종권;노승국;경진호
    • 한국정밀공학회지
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    • 제19권2호
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    • pp.203-212
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    • 2002
  • Active magnetic hearings allow much high surface speed than conventional ball bearings and therefore greatly suitable for high speed cutting. This paper describes a design and test of an active magnetic bearing system with 16-pole radial magnets. The spindle is originally designed for a CNC lathe and driven by outer motor with 5.5 kW power and maximum speed 10,000 rpm. Considering static load condition and geometric restrictions, radial magnet is designed 16-pole type for smaller outer diameter of the spindle system. Dynamic system characteristics such as natural frequency, critical speed, stiffness, damping and system stabilities are simulated with a rigid rotor model including direct feedback controller. The designed spindle system is realized with digital PIDD controller to compensate phase lag of PWM amplifier and magnet coils. With levitation and step response experiment the control system characteristics are tested, and the spindle is rotated up to 10,000 rpm stab1y.

내면연삭기 고속 주축용 원추형 자기베어링시스템 설계 (Design of Cone-Shaped Magnetic Bearing Spindle System for High Speed Internal Grinding Machine)

  • 박종권;노승국;경진호
    • 한국정밀공학회지
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    • 제19권2호
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    • pp.213-219
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    • 2002
  • A cone-shaped active magnetic healing spindle system for high speed internal grinding with built-in motor that has 7.5kW power and maximum rotational speed of 50,000 rpm is designed and built. Using cone-shaped AMB(Active Magnetic Bearing) system, the axial rotor dick and magnets of conventional 5-axis actuating design can be eliminated. so this concept of design provides a simple magnetic bearing system. In this paper, the cone-shaped electromagnets are designed by magnetic circuit theory, and a de-coupled direct feedback PID controller is applied to control the coupled magnetic bearings. The designed crone-shaped AMB spindle system is built and constructed with a digital control system, which has TMS320C6702 DSP, 16 bit AD/DA, switching power amplifier and gap sensors. As the AMB system provides high damping ratio eliminating overshoot and resonance speed, this spindle runs up to 40,000 rpm stably with about 5${\mu}{\textrm}{m}$ of runout.