Browsing by Author "Fong, ZH"

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A method for improved bicycle shifting performance
(1997)
Wang, CC
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Tseng, CH
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Fong, ZH
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交大名義發表
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機械工程學系
The overwhelming majority of bicycles, the most common human-powered vehicles (HPVs), are equipped with sophisticated derailleur systems that serve the same purpose as transmissions in motor vehicles: enabling more efficient use of input power through selection of suitable gear reduction ratios. This paper presents a method for improving the performance of bicycle derailleur systems by modifying sprocket shape to eliminate jerkiness, slippage and rattling noise, and guide chain movement from one gear to another mole quickly and directly. The sprocket modification CAD/CAM program, and an integrated optimization tool, were developed on an IRIS INDIGO/4000 workstation.
An efficient optimum design procedure for bicycle rear derailleurs
(1996)
Hou, YC
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Su, SH
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Tseng, CH
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Fong, ZH
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交大名義發表
The rear derailleur on a multi-speed bicycle guides the running chain rapidly and precisely to a selected freewheel sprocket position without disengagement from the freewheel assembly. Therefore, the design of rear derailleurs is most important for designers. An efficient optimum design procedure for rear derailleurs is presented in this paper. Based on an established mathematical model, a series of optimum design sub-problems derived from the original optimum design problem are formulated and solved to meet all design requirements. The advantage of dividing the original design problem into several sub-problems is that it makes the upper/lower bounds of design variables in each sub-problem easier to determine. This reduces the trial-and-error efforts during iterative searching for optimum solutions. Thus, the design procedure becomes more rapid and efficient. It is worth emphasizing that the design procedure proposed herein is applicable to most known types of rear derailleurs.
An experimental approach characterizing rear bicycle derailleur systems part II: the stability region and its applications
(1998)
Lin, TY
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Tseng, CH
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Fong, ZH
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機械工程學系
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Department of Mechanical Engineering
An important concept in the design procedure of bicycle derailleur systems called the stability region is presented in this study. The stability region properties are introduced, and experimental procedures for stability region determination are proposed. The stability ratio, which is a performance index for the stability region is also defined. Shift-lever characteristics such as indexed point, over-shifting and under-shifting can be determined from the stability region experiments. Design concepts and skills for shift lever design are proposed, and a case study is given for demonstration.
Computer-aided manufacturing of spiral bevel and hypoid gears by applying optimization techniques
(2001-07-04)
Lin, CY
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Tsay, CB
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Fong, ZH
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機械工程學系
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Department of Mechanical Engineering
A mathematical model of an ideal spiral bevel and hypoid gear-tooth surfaces based on the GIeason hypoid gear generator mechanism is proposed. Using the proposed mathematical model, the tooth surface sensitivity matrix to the variations in machine-tool settings is investigated. Surface deviations of a real cut pinion and gear with respect to the theoretical tooth surfaces are also investigated. An optimization procedure for finding corrective machine-tool settings is then proposed to minimize surface deviations of real cut pinion and gear-tooth surfaces. The results reveal that surface deviations of real cut gear-tooth surfaces with respect to the ideal ones can be reduced to only a few microns. Therefore, the proposed method for obtaining corrective machine-tool settings can improve the conventional development process and can also be applied to different manufacturing machines and methods for spiral bevel and hypoid gear generation. An example is presented to demonstrate the application of the proposed optimization model. (C) 2001 Elsevier Science B.V. All rights reserved.
Computer-aided manufacturing of spiral bevel and hypoid gears with minimum surface-deviation
(1998-08-01)
Lin, CY
;
Tsay, CB
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Fong, ZH
;
機械工程學系
;
Department of Mechanical Engineering
The linear regression method to minimize the deviations of a real cut gear-tooth-surface is investigated in this paper. Based on the Gleason hypoid gear generator, a mathematical model of the tooth surface is proposed. Applying the proposed mathematical model, the sensitivities of tooth surface due to the variations of machine-tool setting are also investigated. The corrective machine-tool settings, calculated by using the sensitivity matrix and the linear regression method, are used to minimize the tooth-surface deviations. The minimization problem was solved by using the singular value decomposition (SVD) method. The result of this paper can improve the conventional development process and be also applied to different manufacturing machines and methods. Two examples are presented to demonstrate the proposed methodology. (C) 1998 Elsevier Science Ltd. All rights reserved.
Mathematical model of spiral bevel and hypoid gears manufactured by the modified roll method
(1997-02-01)
Lin, CY
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Tsay, CB
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Fong, ZH
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機械工程學系
;
Department of Mechanical Engineering
Based on grinding mechanism and machine-tool settings of the Gleason modified roll hypoid grinder, a mathematical model for the tooth geometry of spiral bevel and hypoid gears is developed. Since all the machine-tool settings and machine constants are involved in the proposed mathematical model, excellent correlation between the mathematical model and actual manufacturing machines can be obtained. An example is given to illustrate the application of the proposed mathematical model. Surface deviation between a real cut spiral bevel gear surface and the model surface is investigated. Bearing contacts and kinematic errors in the spiral bevel gear set are also studied. Copyright (C) 1996 Elsevier Science Ltd.