标题: | 自行车后变速器系统之理论研究与最佳化设计 Theoretical Analysis and Optimization Design for the Rear Derailleur System on Bicycles |
作者: | 侯怡仲 Ying-Chung Hou 曾锦焕 Ching-Huan Tseng 机械工程学系 |
关键字: | 自行车、后变速器、最佳化设计、数学模式、理论分析;Bicycle, Rear Derailleur, Optimization Design, Mathematical Model, Theoretical Analysis |
公开日期: | 1995 |
摘要: | 自行车的后变速器主要功能在于导引链条至所选择的后齿片以完成换档的 动作。因此如何设计一个良好的后变速器可以精确而且迅速的进行换档动 作乃成为设计者最大的挑战。在本论文中,基于一些基本的假设,导出后 变速器的理论数学模式,此模式将一个实际上为六连杆的机构简化为等效 四连杆机构,再利用几何关系及静力分析求出未知的状态变数值。为验证 此数学模式的正确性,本论文同时发展一实验设备用来量测导链导轮中心 在各档位之空间位置。经由量测值及理论值的比对后发现两者相当吻合, 因而成功的验证理论数学模式之正确性。最后,再利用此数学模式作为分 析工具以进行后变速器的最佳化设计,并利用敏感度分析方法将系统参数 加以适当的分类使得最佳化设计更有效率。本论文所发展的最佳设计程序 可运用于发展一般常见的后变速器。 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. The refore, the design of the rear derailleurs is a most important target for designers. In this study, a mathematical model for the rear derailleurs is developed based on some basic assumptions. It involves modeling a typical rear derailleur as an equivalent four-bar linkage from an original six-bar physical model. Unknown state variables in the model are determined by using geometrical and static analyses. An experiment facility is furnished to verify the validation of the developed model. Good agreement is achieved by comparing the spatial positions of the guide pulley center measured in the experiment and calculated based on the mathematical model at various speed ratios. Thus performance of the rear derailleur can be predicted further based on its corresponding simulated model. Finally, an efficient optimum design procedure for the rear derailleurs is presented. It makes the upper/ lower bounds of design variables easier to determine. This reduces the trial-and-error efforts during iterative searching for optimum solutions. It is worth emphasizing that the design procedure proposed herein is applicable to most known types of rear derailleurs. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#NT840489083 http://hdl.handle.net/11536/61005 |
显示于类别: | Thesis |