Development of Anti-loosening Screw Fasteners

本文提出了一种新型防松螺纹紧固件的螺旋结构、制造方法及其性能评价。松动测试的传统螺钉和所谓的防松螺母首次报告和讨论。它表明，人类还没有成功地防止松动的螺钉紧固件，而不牺牲他们的一些重要功能。松动的机制进行了讨论，并概述了两个主要因素，导致松动。第一种是由于螺栓螺纹和螺母螺纹之间的相对滑动，而第二种是由于螺母的支承表面和紧固材料的表面之间的相对滑动。提出了一种新的螺纹形状，旨在抑制前者的因素，并讨论了一种方法来生产螺栓上的适当的螺纹。新的形状被命名为“步锁螺栓”。“检查具有这种形状的螺栓的性能，以证明这个想法的有效性。

The authors propose a new type of helix for anti-loosening screw fastener, the way to manufacture it and the evaluation of its performance. Loosening tests for conventional screws and so-called anti-loosening nuts are first reported and discussed. It is shown that human beings have not yet succeeded in the prevention of loosening of screw fasteners without sacrificing some of their important features. The mechanism of loosening is discussed and the two main factors that cause loosening are outlined. The first is due to the relative slip between the bolt threads and the nut threads, while the second is due to the relative slip between the bearing surface of the nut and the surface of the fastened material. A new screw shape that aims at suppressing the former factor is proposed and a method for producing the appropriate threads on the bolt is discussed. The new shape is named "Step-Lock Bolt." The performance of the bolt with this shape is examined to prove the efficacy of the idea.