• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.627-631
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• 1993

스크류 압축기는 진동이 적고, 소형이면서 고효율을 유지하기가 용이하다는 특징을 가지고 있으며, 원통형 밀패용기 내에 암,수로터가 서로 반대 방향으로 맞물려 회전하면서, 로터홈과 케이싱 사이에 생기는 공간의 용적이 로터회전에 의해서 가스를 흡입, 압축, 배출하는 합축기 이다. 본 연구는 로터의 치형 함수의 기하학적성질 및 제한사항을 고려하여, 대칭 치형을 치수의 조합과, 원, 점, 직선, 타원을 사용하여 비대칭 치형을 설계하였다. 본 연구의 목적은 설계된 치형과 기존의 치형을 치형 형상의 변화에 따른 특성값 (실라인길이, 누설삼각형, 용적곡선, 흡입 및 토출 홈면적)의 변화에 대하여 연구함으로서 성능검토를 시도하였다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.5
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• pp.572-578
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• 1985

A composite gear with involute-circular are tooth profile and a tooth profile of the rack to cut this gear are theoretictically obtained. The composite gear has involute tooth profile in the vicinity of pitch point and has circular arc tooth profiles at addendum adn dedendum. The contact ratio(M$_{c}$), chordal tooth thickness (chordal tip tooth thickness S$_{t}$, chordal root tooth thickness S$_{t}$) of the composite gear are compared with those of involute gear. When module, number of teeth and pressure angle eqaul, S$_{t}$ of composite gear is much larger than that of involute gear. Under the same conditions, S/sib t/ and M$_{c}$ of composite gear become smaller than those of involute gear.lute gear.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.1-10
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• 1993

A design method of gear tooth profile which can reduce the noise of gear is studied. The tooth profile is generated by combining involute and cycloid tooth curves in which the involute tooth profile is near the pitch point and cycloid tooth profile at the addendum and the dedendum. Considering parameters which have an influence on the reduction of gear noise and building up a design conditions for the noise reduction of gear, the lower-noise combined gear tooth profile is designed. For the check of noise reduction of the combined gear profile, two pairs of combined profile gear, two pairs of involute gear, and a pair of cycloid gear were manufactured by the NC Wire Cutting Machine, and the experiment for measuring of gear noise was carried out on each pair. The noise reduction of the combined profile gear was obtained.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.9 no.1
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• pp.42-46
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• 2000

치아형태라고 하면 따분하고 재미없는 것으로 생각하기 쉽지만, 치과임상에서 아주 중요한 기초를 형성하고 있다. 지대치형성은 치과보철수복의 첫 단계로서, 좋은 지대치형성은 좋은 보철물로 연결된다. 또한 치과보철 수복의 대부분은 원래의 치아형태수복에 맞추어져 있어서, 치아형태와 지대치형성은 많은 상관성을 가지고 있을 것이라고 유추해 볼 수 있다. 그러나 통상적으로 알고 있는 치아형태는 교합변형태로만 인식하고 있어서, 지대치형성시 치아형태가 큰 도움을 주지는 못하는 실정에 있다. 물론 교합면형태도 중요하지만 그외의 여러형태도 치과임상에 있어서 결코 무시할 수 없다. 필자는 지대치형성에서 고려해야 할 치아형태와 임상적 중요성에 대해서 언급하여 치과의사선생님들의 임상에 도움을 주고자 한다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.154-162
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• 1991

In this study, the simulation program is developed where the tooth profile error in internal gear shaping is calculated considering several factors which affect it. This factors are the circular feed of the pinion cutter, the interference by the geometric conditions of the cutter and the internal gear, the deviation from the theoretical involute profile of the cutter and the eccentricity of the cutter and the internal gear. With this program, the effects are investigated which the geometric conditions and the cutting conditions in internal gear shaping have on the tooth profile error of the internal gear. The condition for the minimization of it is derived and then the results of simulation are adequately verified by measurements of internal gears cut by a pinion cutter.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.04b
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• pp.146-150
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• 1993

screw압축기는 진동이 적고, 소형이면도 그효율 유지가 용이하다는 특징을 가지고있으며, 왕복압축기와 같은 crank가 없고 원통형 밀폐용기 내에 암,수 로타가 서로 반대 방향으로 맞물려 회전하면서 로타홈과 케이싱 사이에 생기는 공간의 용적이 로타의 회전에 의해서 가스를 연속적으로 흡입, 압축, 배출하는 용적형압축기이다. 본 연구는 screw 압축기의 성능에 큰 영향을 미치는 로타의 치형함수의 기하학적성질 및 제한사항을 서술하였고, 로타의 형상이 특성값에 미치는 영향을 이론적으로 해석 하기 위하여, 임의의 치형을 갖는 로타를 만들고, 이것과 맞물리는 상대로타의 치형을 설계하여 seal line length와 blow hole area을 계산하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.3
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• pp.315-320
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• 2006

There are many types of reduction drives for industrial applications. In general, high precision speed reducer which has a cycloid or involute teeth profile, used to in robot. Because, it is essential to use precision reduction drives for accuracy of position control on robot system. In this paper, we propose a robot speed reducer(RSR) with straight line teeth profile, which has basically a triangle teeth profile. In new straight line teeth profile, we have a good result for strength, stress and stiffness by using finite element analysis and the results indicate that variation of eccentric coefficient affects the optimal tooth motion, and it can lower the stress and noise.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.7
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• pp.952-956
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• 2007

In industrial site, as the technology of FA developes, many robots can take the place of human labor. Generally, robots require high precision reducers which have cycloid or involute tooth profile. These reducers provide high reduction ratios with low backlash and high accuracy but need a high stiffness of tooth. In this study, to improve the high precision, the cycloid reducers which have straight line teeth profile are used. Also the FEM analysis, which consist of straight line teeth profile, was performed to simulate the stress of teeth profile.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.3
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• pp.295-302
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• 2014

An internal gear pump is required to improve the flow rate and noise. Furthermore, such pumps are durable and small in size. In this study, equations of the rotor shape with multiple profiles (ellipse 1-involute-ellipse 2) were derived, and relevant performance parameters (pressure angle, irregularity, and specific sliding) of the internal gear pump to noise were predicted and compared. Rotor profiles and performance parameters were obtained by a prediction algorithm for theoretical analysis, and the effects between the design parameters and the performance parameters were analyzed. Based on the analysis results of the effects, an optimal design of the rotor profile was proposed, and a noise test of the prototype was performed to evaluate the reliability of the design.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.2
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• pp.169-177
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• 2015

Because technology of the sintering process is highly advanced, the gerotor used in the internal gear pumps of vehicles has advantages for manufacturing complex profiles and obtaining durability and minimization. However, it has been necessary to continuously improve the flow rate and noise of internal gear pumps for better fuel efficiency. The existing rotor was designed using a translation algorithm. This caused a discontinuity of the rotor profile, which had adverse effects on the performance. In this study, to improve the discontinuity of the profile, a new design program using a rotation and translation algorithm was developed, and two types of combined multiple profiles (three-ellipses and ellipse 1-involute-ellipse 2) were generated. Then, the performances (flow, flow rate, specific sliding, and pressure angle) of these profiles were calculated. On the basis of the calculation results for the performances, optimal designs of the two types were carried out and verified by comparing their performances with those of the existing rotor profiles.