• 한국기계가공학회지
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• 제16권3호
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• pp.54-62
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• 2017

When gears mesh, shock and noise are produced as results of tooth error and tooth deformation under load. Transmission error (TE) is the most important cause of gear noise and vibration because TEs affect the changes of the force and the speed of gears. Gear tooth modification research plays a positive role in reducing TE and improving the design level and transmission performance of transmission systems. In high-precision manufacturing gear, gear tooth modification is also commonly used to reduce noise in practical applications. In order to study the accuracy of gear transmission, some empirical gear profile micro-modifications are introduced, and a helical gear pair is modeled and analyzed in RomaxDesigner software to investigate the utility of these modification methods. Some of these will be selected as experimental proposals for gear pairs, and these manufactured gears will be tested and compared in a semi-anechoic room later. The final purpose of this study is to find reasonable and convenient empirical formulae to facilitate improved gear production.

• 한국정밀공학회지
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• 제22권11호
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• pp.111-117
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• 2005

The vibration problems associated with gear coupled rotors have been the focus of much engineering work. These systems are complex and difficult to analyze in that they have the problems associated with conventional rotors plus those additional problems associated with the gear couplings. This paper examines the problems peculiar to the gear mesh. Because of the meshing action of gears, the elasticity of the gear teeth introduces time-varying stiffness coefficients into the governing equations of motion. This means that system response must be thought of in terms of Mathieu-type equations, where multiple-frequency response occur due to the periodic coefficients. The meshing action of the gears also couples the lateral and torsional gear motions. Gear errors, such as tooth profile and spacing errors, produce forces and torque that excite the system at multiple frequencies, some of which are much higher than shaft rotational speed. To investigate how to the time-varying stiffness in the gear teeth and the gear errors act one the dynamic response of the gear coupled rotors, a three-dimensional dynamic model with lateral-tortional oscillation is developed. The harmonic balance technique is employed to solve this mathieu-type problem.

• 한국기계가공학회지
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• 제11권6호
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• pp.195-200
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• 2012

In this study, parameters and requirements of an 120kW class monorail planetary gearbox was analysed and the adaptive planetary gearbox design was selected. The specification of the sun gear, planetary gear and carrier was set and the profile & lead was optimized. The mechanical efficiency of the optimized one and the original one was observed. Dynamo-tester system was used to observe the mechanical efficiency of the planetary gearbox. A dynamo unit was connected with the planetary gearbox which straightened through the motor by a coupling. The standard tooth shape planetary gearbox and modified tooth shape planetary gearbox were used as test pieces and the rotation speed was set from 600 to 6000rpm with 600rpm, 2.5min one step. In order to check the mechanical efficiency of the planetary gearbox, the tests were done as follows. 1) The power loss between driving motor and dynamo tester. 2) Temperature variation by different rotation speeds. 3) Noise variation by different rotation speeds.

• 한국생산제조학회지
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• 제8권5호
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• pp.96-101
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• 1999

This study suggests an algorithm for tooth profile generation of free from curve involute gear, a special gear of which the pitch line is a free curve instead of a circular one. For the first, a methodology for calculation of the tooth curve is developed and formulated Then the formulated algorithm, is programmed for manufacturing and verified by computer graphics. Next the calculated results as changed in to NC codes to apply to wire electric discharge machine(WEDM). Finally, the machined gear is examined in engagement with a standard involute gear.

• 한국가스학회지
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• 제18권6호
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• pp.45-50
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• 2014

본 논문에서는 산업기계 및 로봇산업에 적용할 수 있는 직선 정밀 이송 장치의 구동부를 설계하였다. 동력의 전달방향 및 출력특성은 기존의 Rack-Pinion 타입과 유사하나 구동부에 대하여 새로운 Pin-Pinion Gear 타입을 적용시켜 랙 모듈화를 통한 무한 길이 확장성을 구현하고 고속이송 및 설치의 편의성을 확보할 수 있으며 이러한 Pin-Pinion Gear의 최적물림을 위한 Cycloid 치형 해석을 하였다. 그 결과 Cycloid 치형으로 설계시 핀과 피니언 기어의 백래쉬 및 물림 특성이 적합하여 정밀제어가 가능한 치형으로 분석되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.803-806
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• 1995

The vibration and nosic of gears is causeed by manufacting error,alignment error in assembly, and thr meshing stiffness of gears which changes periodically as the meshing of teeth process. On a pair of power transmission helical gears with profile error, the relation between the characteristics of gear vibration and the profile error type have been investigated by simulating the vibrational acceleration level and calculating the natural frequency. The results show that the profile error decrease the natural frequency by reducing the tool stiffness and that the concave error type increase the vibrationsl level. And this paper describes the effect of the tip relief on the vibrational acceleration level which a pair of helical gears with concave error generates.

• 대한기계학회논문집A
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• 제39권2호
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• pp.169-177
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• 2015

내접형 기어펌프에 사용되는 지로터의 경우, 소결 공정기술의 발달로 복잡한 형상의 가공이 용이하며 내구성과 소형화의 장점이 있으나, 자동차의 연비효율 개선을 위한 유량증대 및 소음저감을 위한 연구가 요구되고 있다. 본 논문에서는 기존의 병진이동에 의한 지로터 치형의 형상조합 알고리즘이 가지는 형상 불연속성을 개선하기 위하여 회전이동 및 병진이동을 이용한 형상조합 알고리즘을 개발하였으며, 이를 토대로 개발된 설계 프로그램을 이용하여 3-타원이 조합된 경우와 타원 1-인벌루트-타원 2 이조합된 경우에 대해 치형형상을 도출하고, 형상에 따른 로터의 주요성능(유량, 유량맥동, 미끄럼률 및 압력각)을 계산하였다. 해석결과를 토대로 조합된 치형형상에 대한 최적설계를 수행하였으며, 기존 치형과의 성능 비교를 통하여 설계의 타당성을 검증하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1241-1242
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• 2013

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 추계학술대회 논문집
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• pp.123-124
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• 2009

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.857-860
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• 1996

The area of gear dynamics has recently been the focus of many studies. A new tooth profile modification was proposed by author for reducing vibration and noise of involute gears. A comparative dynamic analysis of the gear drive with the involute tooth and the modified tooth profile(using cubic splines) is performed to the unuformal transmission error reduces the gear vibration and noise due to less dynamic tooth load variation during the meshing cycle. This work also include a gear design process by the meaning of a practical approach, such as Win95 based simulation program with all using basic geardesign variables. Especially this program enables gear designers to dynamic analysis based on G.U.I.