Patent ID: 7766574

Claim:
A fastener system comprising: two parts aligned along a common axis, the two parts comprising flanges with bearing surfaces extending perpendicularly to said common axis, said flanges comprising through holes evenly distributed about the common axis and positioned to be into register with one another, a plurality of pins, each pin being inserted in a pair of through holes of the flanges and having threaded ends, each pin comprising a collar between said threaded ends of each pin, wherein one of said flanges comprises an annular groove, centered on said common axis, for receiving the collar of each pin, the groove comprising two cylindrical walls coaxial with said common axis and radially spaced by a predetermined distance, wherein each of the collars comprises two plane side faces which form a first angle (A) that is substantially equal to but less than a second angle (B) formed by lines extending from the common axis to centers of two adjacent through holes of said one flange, and wherein each collar is prevented from bearing against the radially spaced cylindrical walls of the groove by two of the collars respectively being on either side of said each collar, and wherein said each collar is blocked by a planar contact area between the plane side faces of said each collar and the plane side faces of said two collars respectively being on either side of said each collar so as to prevent the pins from turning.