• 제목/요약/키워드: 사이클로이드

검색결과 38건 처리시간 0.028초

트랙션이 없는 커스프 균열의 열응력세기계수에 관한 연구 (Thermal Stress Intensity Factors for Traction Free Cusp Cracks)

  • 이강용;최흥섭
    • 대한기계학회논문집
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    • 제12권2호
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    • pp.286-294
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    • 1988
  • 본 논문에서는 Bogdanoff가 제시한 열응력 관계식을 이용하여 균일 열유동을 받는 무한체내에 존재하는 균열에 대해서 균열표면에 자유트랙션조건과 열경계 조건을 부여하여 TSIF를 구하고자 한다. 다루고자 하는 커스프 균열의 형태는 하이포사이클로이드형(hypocycloid type), 대칭익형(symmetric airfoil type), 그리고 대칭입술형(symmetric lip type)이다.

Hertz 접촉이론을 이용한 사이클로이드 감속기의 비틀림 강성해석 (Torsional Stiffness Analysis of a Cycloid Reducer using Hertz Contact Theory)

  • 이상엽;박제승;안형준;한동철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.816-821
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    • 2005
  • The cycloid reducer has very high efficiency, high ratios, high stiffness and small size, in comparison with a conventional gear mechanism, which makes it an attractive candidate for limited space and precision application such as industrial robot. There are several publications on analysis and design of the cycloid reducer, however, it was assumed that the contact stiffness of pin rollers and cycloid disk is constant regardless of their contact geometry. Moreover, the torsional stiffness of the cycloid reducer couldn't be calculated due to the assumption. In this paper, we present a new procedure of calculating torsional stiffness of the cycloid reducer using Hertz contact theory. First, conventional force analysis of the cycloid reducer is briefly reviewed. Then, iterative numerical calculation procedure of the contact stiffness is proposed based on the Hertz contact theory where the contact stiffness depends on the contact force. In addition, total torsional stiffness of the cycloid reducer is estimated considering its rolling element bearing stiffness. The torsional stiffness of the cycloid reducer is dominated by the rolling element bearing stiffness since the contact stiffness of the cycloid disk is too large.

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커스프균열형 강체함유물의 열응력 세기계수에 관한 연구 (Thermal Stress Intensity Factors for Rigid Inclusions of Cusp Crack Shape)

  • 이강용;최흥섭
    • 대한기계학회논문집
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    • 제12권3호
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    • pp.497-504
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    • 1988
  • 본 연구에서는 트랙션이 없는 커스프 균열에 적용한 방법을 확장하여 무한대 에서 균일열유동을 받는 무한체내에 하이포사이클로이드형(hypocycloid type), 대칭이 기형(symmetric airfoil type), 대칭입술형(symmetric lip type) 강체 함유물이 존재 하고 그 표면은 단열되거나 상대온도가 영으로 주어지는 경우에 대해서 열응력세기계 수(thermal stress intensity factor이하에서 TSIF로 표기함)를 유도하고자 한다.

이단 사이클로이드 드라이브의 비틀림 강성 (Torsional Rigidity of a Two-stage Cycloid Drive)

  • 김경홍;이춘세;안형준
    • 대한기계학회논문집A
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    • 제33권11호
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    • pp.1217-1224
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    • 2009
  • This paper presents a finite element (FE) analysis of the torsional rigidity of a two-stage cycloid drive. The cycloid disk makes contact with a number of pin-rollers simultaneously and eccentric shafts transmit not only torque of the spur gear stage to the cycloid disk, but also that of the cycloid disk to the output disk. Contacts between the disk and pin-rollers are simplified as linear spring elements, and the bearing of eccentric shaft is modeled as a rigid ring that has frictional contact to the disk and an elastic support. FE analysis for an ideal solid cycloid drive was performed and verified by a theoretical calculation. Accurate contact forces were then estimated by iterating between FE analysis for contact forces and Hertz theory calculations for nonlinear contact stiffness. In addition, torsional rigidity of the cycloid drive is analyzed to show that the bearing and nonlinear Hertz contact theory should be considered in analysis and design of a cycloid drive, which was verified with experiments. Finally, the effects of contact stiffness, bearing stiffness and cycloid disk structural stiffness according to the cycloid disk rotation on the torsional rigidity were investigated.

다물체 모델링을 이용한 2단 유성식 외륜 고정형 사이클로이드 감속기의 진동특성분석 (Vibration Analysis of Planetary Fixed Outer-ring Type Cycloidal Speed Reducer by using Multi-body Modeling)

  • 김홍기;이기복;유홍희
    • 한국소음진동공학회논문집
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    • 제23권3호
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    • pp.234-239
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    • 2013
  • There are many types of speed reducer for industrial uses. However the cycloid speed reducer is widely used in manipulators based on excellent performance of low backlash, high reduction ratio and compact size. It is essential to use precision speed reducer for accuracy of position controls on robot systems and electric vehicles. The cycloid speed reducer has a eccentric rotating motion and offset to avoid some problem of assembly, so it has a disadvantage for vibration. In this paper, a multi-body dynamic model is developed for a cycloid speed reducer and the dynamic behaviors of the reducer are investigated. The cycloid speed reducer consists of cycloidal plate gears, housing gear, input shaft, output pin and shaft, and eccentric bearings. Using a CAD program, each component of cycloid reducer is modeled based on the offset and eccentric. Multi-body simulations using Recurdyn and test using a rig tester are performed. As a result, the pin reaction force and the amplitude of housing displacement are increased by the larger offset and smaller eccentric value of cycloid reducer.

사이클로이드 및 폴리서클 곡선을 이용한 내접형 기어펌프용 치형 개발 (Development of Rotor for Internal Gear Pump using Cycloid and Polycircular-arc Curves)

  • 김민수;이현우;정성윤;김철
    • 한국정밀공학회지
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    • 제29권9호
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    • pp.1003-1011
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    • 2012
  • A new type of gerotor developed in this paper has the inner rotor designed by inserting a polycircular-arc between the hypocycloid and epicycloid curves, and we also suggest that the outer rotor be designed using the closed-form equation for the inner rotor and a method of modification. Thus, it is possible to design a gerotor for which there is no cusp and loop, as in this case undercut is prevented. We developed automated program for rotor design and calculation of the flow rate and flow rate irregularity. And we also demonstrate the superior performance of the gerotor developed in this study by analyzing the internal fluid flow using a commercial computation fluid dynamics-code (CFD).