• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.276-286
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• 2000

최근 수요가 증가되고 고층건물시 사용되는 lift car 구조물 내부에 많은 결함이 발견되고 있는 것으로 보고되고 있다 특히 lift car의 핵심부품이라 할 수 있는 피니언 축에 발생한 결함으로 인하여 이를 사용하지 못함으로써 건설공사 공기 준수에 막대한 영향을 미치고 있으며 또한 인명사고의 위험성까지 내포하고 있다.(1) 따라서 lift car의 안전성과 신뢰성 확보는 건설공사의 경제성 향상과 인명보호를 위하여 매우 중요하다.(중략)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2387-2396
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• 2000

Wear and operation characteristics of Nylon and Acetal pinion against steel gear were studied to gain a better understanding of their tribological and mechanical behavior. Tests were conducted with power circulating gear test rig under unlubricated conditions. Specific wear rates were measured as a function of applied load and total revolution. The worn tooth surfaces were examined with a profile projector and camera. Nylon pinion showed lower specific wear rates than Acetal pinion, but it revealed breakage at high load. Principal wear depths were developed at tooth tip and below the pitch line of pinion. Life estimation for the Nylon pinion was made by taking into account steel gear equivalent Hertz stress and average sliding velocity. The dominant wear mechanisms were adhesion and abrasion.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.2
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• pp.283-289
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• 2012

Cam rack pinion (CRP) system which consists of cam rack and roller pinion transforms the rotation motion into linear one. The roller pinion has the plurality of rollers and meshes with its conjugated cam rack. The exact tooth profile of the cam rack and the non-undercut condition to satisfy the required performance have been proposed by introducing the profile shift coefficient. The load stress factors are investigated by varying the shape design parameters to predict the gear surface fatigue limit which is strongly related to the gear noise and vibration at the contact patch. The results show that the pitting life can be extended significantly by increasing the profile shift coefficient.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.4
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• pp.387-393
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• 2012

A roller rack pinion (RRP) system, which consists of a rack-bar and a cam pinion, transforms a rotation motion into a linear one. The rack-bar has a series of roller trains, and meshes with the cam pinion. This paper first proposes the exact tooth profile of the cam pinion and the non-undercut condition to satisfy the required performance by introducing the profile shift coefficient. The paper then investigates the load stress factors under various shape design parameters to predict the gear surface fatigue limit, which was strongly related to the gear noise and vibration at the contact patch. The results show that the pitting life can be extended significantly with an increase in the profile shift coefficient.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1453-1459
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• 2011

A roller pinion gear (RPG) system composed of either a pin or a roller and its conjugated cam gear can improve the gear endurance from that of a conventional gear system by reducing the sliding contact while increasing the rolling motion. In this paper, we first proposed the exact cam gear profile and the self-intersection condition obtained when the profile shift coefficient is introduced. Then, we investigated the Hertzian contact stresses and the load stress factors while the varying the shape design parameters to predict the gear surface fatigue life, which is strongly related to the gear noise and vibration at the contact patch. The results show that the pitting life can be extended significantly by increasing the profile shift coefficient.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.1
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• pp.95-101
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• 2012

An internal type roller ring gear(RRG) system composed of either a pin or a roller ring gear and its conjugated cam pinion can improve the gear endurance from that of a conventional gear system by reducing the sliding contact, while increasing the rolling motion. In this paper, we first proposed the exact cam gear profile and the self-intersection conditions obtained when the profile shift coefficient is introduced. Then, we investigated contact stresses and surface pitting life to fmd characteristics for surface fatigue by varying the shape design parameters. The results show that the pitting life can be extended significantly by increasing the profile shift coefficient.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.3
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• pp.299-305
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• 2017

Gate-lifting devices in small- to mid-sized sluice gates mostly employ the mechanical roller rack pinion (RRP) system. This RRP system, which consists of a rack-bar and a pinion, transforms a rotation motion into a linear one. The rack-bar has a series of roller trains that mesh with the pinion. In this study, we adopt an exact involute-trochoid tooth profile of the pinion to obtain a higher contact fatigue strength using the profile modification coefficient. Further, we determine the contact forces and investigate Hertz contact stresses to predict the pitting life of the pinion according to varying the shape design parameters. The results indicate that the design fatigue life of an RRP system for sluice gate can be achieved only when the design value of the profile modification coefficient reaches or exceeds a certain level.