Patent ID: 6135689
Filing Date: 2000-10-24
Classification: F16B

Abstract:
A combination of an earth bolt and a nut, said earth bolt comprising;a body having a threaded portion that includes a plurality of threads; anda plurality of lock portions formed by deforming crests of respective ones of said threads to have a cross section of a trapezoidal-shape over an arcuate region of 10 to 40 degrees about an axis of said earth bolt, said lock portions being formed at intermediate positions between ends of the threaded portion;wherein said lock portions have a thread angle which is smaller than a thread angle of a portion of the threaded portion whose threads do not have deformed crests; andwherein a lowermost one of the lock portions is positioned below an underside of the nut when the earth bolt is screwed into the nut;whereby a favorable electrical conductivity between the earth bolt and the nut is achieved.