Fastener assembly

摘要

An improved fastener assembly includes an externally threaded member or bolt having a thread convolution with a relatively long trailing flank surface and a relatively short leading flank surface. An internally threaded member or nut also has a thread convolution with a relatively long trailing flank surface and a relatively short leading flank surface. The nut is grooved to provide an expandable section. When the nut and bolt are tightened, the relatively long trailing flank surfaces of the thread convolutions cause the grooved portion of the nut to expand to completely fill a hole. The opposite end of the nut is contracted to clamp against a thread convolution on the bolt. In one embodiment of the invention, a relatively short leading flank surface of the bolt extends at an acute angle to the relatively short leading flank surface of the nut to provide clearance between the internal and external thread convolutions. In another embodiment of the invention, the grooves in the nut extend only part way through the thread convolution in the nut.