Elastic stability of helical springs at a compression larger than original length
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A former statement that, as to the behaviour of helical compression springs in respect of elastic stability, it is quite immaterial whether the ends of the springs are hinged, constrained parallel or clamped, appears to be true only for compressions smaller than the original spring length. For larger compressions, on the other hand, the differences occurring for the various end conditions are found to be quite characteristic. Since we were able to realize a (cylindrical) spring with a compression larger than original length, by simply turning it inside out, the new theoretical results found for this region of compressions could be verified by experiment. These experiments demonstrated the remarkable toppling over of the coils which accompanies the transition from the stable to the unstable state. Moreover, they confirmed the existence of the characteristic differences in the behaviour of the spring for the various end conditions, though qualitatively only. An explanation for the numerical deviations occurring is only mentioned here and will be discussed more fully in a second paper.
KeywordsExternal Load Unstable State Deflection Angle Original Length Elastic Stability
- 1).This paper was prepared for the 7th international Congress of applied Mechanics, held in London in September 1948.Google Scholar
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