Patent ID: 7243963

Claim:
A security seal comprising a locking body and a thread having a first end attached to the body and a second free end, the body having an entry opening for inserting the second end of the thread into the body and locking means in the interior of the body that allow the second end of the thread to pass in the insertion direction and prevent it from being withdrawn in the opposite direction, said locking means having: first and second fixed and substantially flat surfaces facing each other, but angularly diverging from each other in said thread-insertion direction, from a region adjacent said opening; at least one movable wedge element having, on one side, a substantially flat guide surface, adapted to slide along said first fixed surface, and a substantially flat thread-locking surface, on an opposite side of the wedge element, the thread-locking surface being angularly divergent with respect to the guide surface in the thread-insertion direction and defining one side of a passage for the thread within said body, the movement of the tread in the insertion direction through said opening causing displacement of the guide surface of the wedge element along the first fixed surface in the insertion direction, with the consequent increase of the width of the passage for the thread, and the movement of the thread in the opposite direction towards said opening causing displacement of the guide surface of the wedge element also in this direction, thus narrowing the passage for the thread on the side of the thread-locking surface and locking the thread against its withdrawal from the body, said opening having a cross-section substantially equal to that of said thread; and flexible spring means having a first end integrally connected to said body and a second opposite end integrally connected to said at least one moveable wedge element so as to permit said displacement in the thread-insertion direction and in the opposite direction, said at least one moveable wedge element, said spring means and at least a part of said body comprising a single infection molded part.