Patent ID: 7174811
Filing Date: 2007-02-13
Classification: B25B,F16B

Abstract:
1. An asymmetric threaded open fastener for being turned by a wrench, said fastener having a fastener central axis and generally radially extending, outwardly directed fastener splines separated by alternating fastener recesses, each fastener spline comprising: a first surface on a first side of said fastener spline, a second surface on a side opposite from said first side of said fastener spline; inner joining surfaces interconnecting the inner ends of each of said first surfaces and the second surface of an adjacent spline, said inner joining surfaces being curved at said respective ends of said inner joining surfaces where they join the respective first and second surfaces, for engaging a corresponding wrench and applying a lower amount of concentrated stress to a cooperating wrench than would linear inner intersections having sharp corners.