Patent ID: 6139237
Filing Date: 2000-10-31
Classification: F16B

Abstract:
A metallic fastening member formed of one piece of a metal material, comprising a cylindrical shaft and a flange extending outward from a first end of said shaft,said shaft including a portion to be caulked at a second end opposite to said first end, and a shaft main portion that is continuous to said portion to be caulked and that extends toward said first end,said shaft having a wall including a thin-walled portion having a partially reduced wall thickness, which comprises a first groove extending in a direction around at least any of an outer peripheral face and an inner peripheral face in a substantially annular region constituting a perimeter of said shaft in the vicinity of an interface between said shaft main portion and said portion to be caulked, andsaid thin-walled portion maintaining a strength so that said thin-walled portion does not fracture under application of an axially directed force that is exerted in the state when said fastening member is fastened to a workpiece in a caulked state, and so that said thin-walled portion is fractured by application of an axially directed tensile force greater than a predetermined level to allow said shaft to be separated into two parts along said thin-walled portion.