曲軸與機構的應用

Abstract

曲柄軸設計的好壞，將會影響其引擎的平衡問題，在引擎運作時會產生各種慣性力，在最佳化設計中，引擎運作時所有的慣性力之合在任何轉速下都必須為零，如果慣性力何不為零，就會開始產生偏移的力矩，導致內部機械零件不斷震動，可能致使零件損毀，也會分散引擎運作的力，導致效率降低。 本研究我們探討了五種機構的簡單分析，曲柄、羅斯軛、蘇格蘭軛、急回機構、肘節機構，比較其特性，了解到它們的長處與適用的地方。 本次分析我們比較了曲柄和羅斯軛兩個機構放在同樣汽缸尺寸的γ型史特靈引擎上，為在不同曲柄軸的設計下，對於同轉速的情況下，不同曲柄軸相對於活塞的運作速度，判別出哪個機構較適合此引擎。 結果發現，使用曲柄的引擎轉速一樣但活塞速度較慢就可帶動，而羅斯軛則需要較大的速度，所以可以判定在此引擎上曲柄較羅斯軛適合。

The design of the mechanism is the most important of an engine. It will affect the balance of the engine. With a engine is operating then will bring a lot of inertial forces, in the best design, the total inertial forces of engine producing at any speed must to be zero. If the inertial forces are not at the balance state, will make the torque, then the parts of the mechanical maybe to shock more, and cause the damage to the parts, or it could disperse the thrust of the engine that reduce the efficiency. In this study, we explored a simple analysis of five mechanisms, Crank, Ross Yoke, Scotch Yoke, Quick return mechanism, Toggle mechanism, compare their features, to understand their strengths and application at where. At the last, we analyzed and compared the two mechanisms, about Crank and Ross Yoke, we take the tow mechanisms in the same size gamma type stirling engine, let the flywheel at the same rotation rate, in order to find the efficiency at the same conditions but the different mechanisms, to decide the which one is the better for this type of the engine. In the result, we find the piston velocity of the Crank Case is lower than the Ross Yoke Case, then we can defined the Crank is better than the Ross Yoke in the gamma type stirling engine.