헬리컬기어의 동적해석을 통한 전달오차 예측

이정석(Jeongseok Lee),윤문영(Moonyoung Yoon),부광석(Kwangsuk Boo),김흥섭(Heungseob Kim) 대한기계학회 2016 大韓機械學會論文集A Vol.40 No.12

기어소음의 근본적인 원인은 전달오차로 인해 발생하게 된다. 전달오차는 기어가 맞물릴 때 발생하는데 크게 정적전달오차와 동적전달오차가 있다. 이러한 오차들은 기어 이빨의 처짐 또는 치면 마찰에 의해 발생하고 이 요인들이 원인이 되어 기어 시스템에 진동이 발생하게 된다. 그리고 이 진동이 기어의 축으로 이동하게 되어 축을 떠받치고 있는 베어링에 전달되고 베어링에 전달된 가진은 최종적으로 기어의 케이싱으로 이동하게 되어 소음을 방출하게 된다. 본 논문에서는 이러한 전달오차에 의해 발생하는 최대 굽힘응력을 가지는 롤각을 찾기 위한 응력해석을 수행되었다. 본 논문에서는 이론적 바탕으로 설계되어 인볼류트 곡선을 가진 기어와 수정된 치형을 가진 기어의 전달오차에 대한 해석을 진행하였다. 또한, 급작스러운 작동이나 큰 백래쉬로 인해 발생하는 충격강도에 대한 영향을 알아보기 위해 유한요소해석을 통해 각각 정적 최대굽힘응력과 동적 최대굽힘응력의 결과를 이용하여 충격인자 값을 예측해 보았다. The fundamental reason for gear noise is transmission error. Transmission error occurs because of STE (static transmission error) and DTE (dynamic transmission error), while a pair of gears is meshing. These errors are generated by the deflection of the teeth and the friction on the surface of the teeth. In addition, the vibration generated by transmission error leads to excited bearings. The bearings support the shafts, and the noise is radiated after exciting the gear casing. The analysis of the contact stress in helical gear tooth flanks indicates that it is due to impact loading, such as the sudden engagement and disengagement of a gear. Stress analysis is performed for different roll positions, in order to determine the most critical roll angle. Dynamic analysis is performed on this critical roll position, in order to evaluate variation in stresses and tooth contact force, with respect to time. In this study, transmission error analysis was implemented on a spur and helical gear with involute geometry and a modified geometry profile. In addition, in order to evaluate the intensity of impact due to sudden engagement and significant backlash, the impact factor was calculated using the finite element analysis results of static and dynamic maximum bending stresses.

기어 전달오차 계측 시스템 개발 및 검증에 관한 연구

문석표(Seok-Pyo Moon),이주연(Ju-Yeon Lee),문상곤(Sang-Gon Moon),김수철(Su-Chul Kim) 한국기계가공학회 2021 한국기계가공학회지 Vol.20 No.12

The purpose of this study was to develop and verify a precision transmission error measurement system for a gear pair. The transmission error measurement system of the gear pair was developed as a measurement unit, signal processing unit, and signal analysis unit. The angular displacement for calculating the transmission error of the gear pair was measured using an encoder. The signal amplification, interpolation, and transmission error calculation of the measured angular displacement were conducted using a field-programmable gate array (FPGA) and a real-time processor. A high-pass filter (HPF) was applied to the calculated transmission error from the real-time processor. The transmission error measurement test was conducted using a gearbox, including the master gear pair. The same test was repeated three times in the clockwise and counterclockwise directions, respectively, according to the load conditions (0 - 200 N·m). The results of the gear transmission error tests showed similar tendencies, thereby confirming the stability of the system. The measured transmission error was verified by comparing it with the transmission error analyzed using commercial software. The verification showed a slight difference in the transmission error between the methods. In a future study, the measurement and analysis method of the developed precision transmission error measurement system in this study may possibly be used for gear design.

기어시스템에서 설계변수에 따른 전달오차와 물림강성 해석

김병준,이영훈,김형준,부광석,김흥섭 한국정밀공학회 2022 한국정밀공학회지 Vol.39 No.4

The gear has a wide range of transmitted force as various gear ratios are possible using a combination of teeth. It can transmit power reliably and cause relatively little vibration and noise. For this reason, the application of reducers of electric vehicles is being expanded. Vibration noise generated from gears is propagated into the quiet interior of a vehicle, causing various claims. In most gear studies, transmission error has been pointed out as the main cause of vibration noise of gears. Transmission errors have various causes, including design factors, manufacturing factors, and assembly factors. In general, when predicting transmission error through finite element analysis, design factors play an important role without considering manufacturing factors or assembly factors. In this study, relationships among important design variables (gear module, compensation rate, load torque, and transmission error) in gear design were investigated using analytical and experimental methods. In addition, a method of predicting gear meshing stiffness through the predicted gear transmission error was proposed to obtain variation of meshing stiffness due to changes of gear design parameters.

〈학술논문〉 가공 오차를 고려한 사이클로이드 치형 감속기의 각도 전달 오차에 대한 연구

김경록(Kyungrok Kim),홍일화(Ilhwa Hong),김영환(Younghwan Kim),임흥순(Heungsoon Lim) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11

In this study, the angular transmission error(A.T.E.) for the reducer using cycloid gear was analyzed by consideration of the manufacturing error of main components. It was constructed that the analytic model of the A.T.E was based on equivalent spring system from the Hidaka's research. The manufacturing errors of the components were defined for the analysis. To obtain the defined variables, a measuring method of the manufacturing errors was presented and a geometrical method was defined to transform the measured data into input data. The ATE. of the reducer was estimated from the obtained variables using the method. In order to verify the analytic result, the A.T.E. was measured by an experimental method. As a result of comparison of both data, it was found that analytical and experimental results were similar in the error range of 10%.

전기구동 다목적 승용관리기의 안정성 연구

임동우 ( Dongu Im ),이유진 ( You-jin Lee ),김재현 ( Jae-hyun Kim ),문동주 ( Dong-joo Moon ),박영준 ( Young-jun Park ) 한국농업기계학회 2023 한국농업기계학회 학술발표논문집 Vol.28 No.2

상용차와 더불어 농업용 주행체의 전동화가 가속됨에 따라 기어 기인 소음에 대한 관심이 커지고 있다. 특히, 엔진 폭발의 masking effect에 의해 문제가 되지 않았던 기어물림주파수 영역의 소음에 대한 문제가 제기되고 있다. 기어물림주파수 영역의 소음은 기어 쌍의 전달오차에 의해 발생하며, 이는 기어 치의 탄성변형과 인볼루트 치형으로부터의 기하학적인 편차에 의해서 발생한다. 이를 예측하기 위해서는 시험적인 방법, 유한요소법, 해석적인 방법이 있다. 시험적 방법은 이론적으로는 가장 정확한 방법이라고 여겨지나, 실제로는 제작 및 조립 오차에 의한 영향 때문에 순수하게 기어에 의해 발생한 전달오차를 확인하는데 어려움이 있다. 유한요소방법은 실제 기어 쌍의 형상을 모델링하여 접촉해석을 통해 전달오차를 도출할 수 있기 때문에 제작 및 조립 오차와 치형 오차 등을 정확하게 반영하여 기어를 해석할 수 있다는 장점이 있지만 많은 계산 시간이 필요하다는 단점을 가지고 있다. 이러한 한계점을 극복하기 위해서 본 연구에서는 해석적 방법과 부분적으로 유한요소를 적용하여 전달오차를 예측하였다. 기어물림주파수 영역에서의 전달오차 특성을 예측하기 위해 기어의 블랭크, 굽힘 강성에 대해서는 유한요소기법을, 접촉강성을 위해서는 Hertzain 접촉이론을 기반한 해석적 기법을 적용하였다. 또한 헬리컬 기어의 제작오차를 해석모델에 반영하기 위해 CNC 장비를 이용하여 실제 기어의 3차원 치형을 측정하고 이를 해석 모델에 반영하였다.

사이클로이드 치형 감속기의 가공 및 조립 오차가 각도전달오차에 미치는 영향에 관한 연구

홍일화(Ilhwa Hong),김경록(Kyungrok Kim),김영환(Younghwan Kim),임흥순(Heungsoon Lim),정성현(SungHyun Jung) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.4

In this paper, parameters that have dominant effects on angular transmission error(A.T.E.) of reducer with cycloid tooth profile are identified, and reduction of the A.T.E. is experimentally confirmed by manufacturing error modification. For impact assessment of the A.T.E. on main components, series of the manufacturing errors are suggested and the A.T.E. is estimated in order to find dependent elements from equivalent analysis model. From the analytical result, we could make out that the A.T.E. is mainly caused by the manufacturing errors of hole and tooth profile in cycloid gear. It is also found that the A.T.E. is influenced by the assembly errors of hold flange and output shaft in carrier. It is experimentally verified that these influence factors have considerable effect on the A.T.E.

기어구동계의 정렬불량 해석

장용훈 ( Yong-hoon Chang ) 한국고등직업교육학회 2002 한국고등직업교육학회논문집 Vol.3 No.2

Improper aligning of shafts often leads to transmission error, which causes severe vibration problems in many rotating machines. Misalignment condition is always present in gear driving system for practical applications. In this study, nonlinear dynamic characteristics of the gear driving system due to misalignment were investigated. The results showed that the gear meshing stiffness was decreased but transmission error was increased in case of misaligned gear. Transmission error was calculated for spur gear and bearing stiffness was also calculated. The relationship between force and displacement showed linearity, but one of force and stiffness showed nonlinear shape. A gear driving system was modeled and the gear signal was investigated in the cases of perfect alignment, misalignment, and bearing-housing deformation.

전달오차를 이용한 물리기반(Physics-Based) 기어고장진단 이론연구

박정호(Jungho Park),하종문(Jongmoon Ha),최주호(Jooho Choi),박성호(Sungho Park),윤병동(Byeng D.Youn) 한국소음진동공학회 2014 한국소음진동공학회 학술대회논문집 Vol.2014 No.10

Transmission error (TE) is defined as “the angular difference between the ideal output shaft position and actual position”. As TE is one of the major source of the noise and vibration of gears, it is originally studied with relation of the noise and vibration of the gears. However, recently, with the relation of mesh stiffness, TE has been studied for fault detection of spur gear sets. This paper presents a physics-based theory on fault diagnostics of a planetary gear using transmission error. After constructing the lumped parameter model using DAFUL, multi-body dynamics software, we developed a methodology to diagnose the faults of the planetary gear including phase calculation, signal processing. Using developed methodology, we could conclude that TE could be a good signal for fault diagnostics of a planetary gear.

전달오차의 EEMD적용을 통한 기어 결함분류연구

박성호,최주호 한국전산구조공학회 2017 한국전산구조공학회논문집 Vol.30 No.2

In this paper, classification of spall and crack faults of gear teeth is studied by applying the ensemble empirical mode decomposition(EEMD) for the gear transmission error(TE). Finite element models of the gears with the two faults are built, and TE is obtained by simulation of the gears under loaded contact. EEMD is applied to the residuals of the TE which are the difference between the normal and faulty signal. From the result, the difference of spall and crack faults are clearly identified by the intrinsic mode functions(IMF). A simple test bed is installed to illustrate the approach, which consists of motor, brake and a pair of spur gears. Two gears are employed to obtain the TE for the normal, spalled, and cracked gears, and the type of the faults are separated by the same EEMD application process. In order to quantify the results, crest factors are applied to each IMF. Characteristics of spall and crack are well represented by the crest factors of the first and the third IMF, which are used as the feature signals. The classification is carried out using the Bayes decision theory using the feature signals acquired through the experiments.

치형수정을 통한 기어열 전달오차해석

성은제(Eunje Seong),박준영(Junyoung Park),김현찬(Hyunchan Kim),김기태(Kitea Kim) 한국자동차공학회 2018 한국자동차공학회 지부 학술대회 논문집 Vol.2018 No.5