陳達仁臺灣大學：機械工程學研究所林博揚Lin, Po-YangPo-YangLin2007-11-282018-06-282007-11-282018-06-282007http://ntur.lib.ntu.edu.tw//handle/246246/61159靜平衡機構(static balance mechanism)能夠使機構在運動過程中任何停駐位置均為靜平衡狀態，在日常生活中已廣泛應用於支撐或取放，例如: 檯燈、手術燈支撐架、監視器支撐架等。本論文利用基底安裝(base-attached)之拉伸彈簧應用於平面一個自由度之靜平衡連桿機構設計。相較於前人所做的研究，依照本文所提出的設計方法，可以在不外加平行輔助桿件(parallel auxiliary link)的情況下直接的平衡一個一般四連桿機構系統中的負載重量；本文利用複數向量(complex vector)的表示法將平面二連桿與四連桿機構之重力位能表示出來，辨識位能系統中的獨立變數，對應地加入彈簧。由能量的觀點，系統中的總位能若能不隨機構運動而保持恆常不變，系統即達到所謂的靜平衡狀態，藉由加入對應彈簧之彈力位能變化與機構質心運動所造成之重力位能變化相作抵銷，可得彈簧設計函數。由設計函數得到包括最少彈簧數、彈簧彈性係數、彈簧安裝位置、角度與長度等安裝條件。承接四連桿的所推導出來之平衡方程式，本文提供了四連桿傳輸機構與波氏直線機構(Peaucellier straight line linkage)的設計範例；四連桿的傳輸機構給予已知的幾何構型、桿件與負載質心位置，在加入彈簧後使機構在傳遞重物的過程無需依靠額外的制動力就能維持給定之初速度；八桿之波氏直線機構藉由加入彈簧能補償機構桿件數較多所造成系統的負荷，同時也提供了四連桿以外所延伸的多迴路靜平衡機構。兩範例都提供了軟體的模擬結果作為驗證。Design of statically balanced, planar four-bar linkages with base-attached springs is presented. This design is based on the methodology of conservation of potential energy, formulated by the use of complex number notations for vectors. Minimal numbers of springs required for the two- and four-bar linkages are first identified by the number of independent variable vectors existed in the formulation of the gravitational potential energy. Spring constants and installed angles of springs are then determined by setting the variation of the total gravitational and elastic potential energy to be zero. Derived from the design conditions of general four-bar linkages, designs of statically balanced parallelograms are also accomplished. A transportation device of a general four-bar is given as an example to illustrate the achievement of a spring balancing mechanism. And an eight-bar Peaucellier straight line linkage is demonstrated as an example of a multi-loop linkage system to be applied with the proposed design methodology.Chapter 1 Introduction 1 1.1 Background 1 1.2 Overview of related works 3 1.3 Motivation and preview 7 Chapter 2 Two-bar Spring Balancing Linkage 9 2.1 Introduction 9 2.2 Feasible spring installing conditions 9 2.3 Summary 16 Chapter 3 Four-bar Spring Balancing Mechanism 17 3.1 Introduction 17 3.2 Feasible spring installing conditions 17 3.2.1 General spring balancing linkage 17 3.2.2 Spring balancing linkage of parallelograms 23 3.3 Summary 27 Chapter 4 Numerical Examples of Four-bar Spring Balancing Linkages 29 4.1 Introduction 29 4.2 Application on a transportation linkage 29 4.3 Application on a Peaucellier’s straight-line linkage 33 4.4 Summary 39 Chapter 5 Conclusions and Future Work 40 5.1 Conclusions 40 5.2 Future work 40 References 42 Appendix 45 A1. Multiplication of two complex numbers in vector form 45 A2. Elastic potential energy in multiplication form of complex numbers 45 A3. Conditions for zero summation of two complex numbers 471117607 bytesapplication/pdfen-US靜平衡機構拉伸彈簧平行機構四連桿機構static balancespringplanar parallel linkagesthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/61159/1/ntu-96-R94522635-1.pdf