Self-Locking Screwing Attachment Device And Assembly Provided With Same

摘要

A nut for securing first and second pipe end-pieces together includes a nut lock having a stop member secured to the nut body, and a second element which is rotatable inside the nut body and having a locking feature adapted to lock onto a corresponding locking structure of the second end-piece. The stop member and the second element include corresponding face teeth which are urged to intermesh by an axial compression spring. At or near the tightened condition of the assembly, the second element is locked onto the second end-piece so that rotation of the nut is possible only if the torque applied exceeds a given threshold, for which the face teeth jump over each other while the spring is alternately stressed. A compact design is obtained with the lock positioned at the rear of the nut thread. The clamping face is axially between the nut thread and the lock.

主权项

1. A unitary self-locking screwing attachment device for being part of an assembly having locking structure and for engaging a threaded member of the assembly, the attachment device comprising:
a first element having a threaded body for thread engagement with the threaded member during screwing and unscrewing towards and away from a tightened condition, respectively; and a lock comprising:
a second element rotatably and captively supported onto said threaded body and provided with a locking feature that engages the locking structure at least when the assembly is in or close to the tightened condition;a stop member rotatably secured to said threaded body;a releasable coupling means arranged for releasably coupling said stop member and said second element for common rotation; andspring means for resiliently activating said releasable coupling means; wherein said releasable coupling means and said spring means are configured and arranged to allow relative rotation of said stop member and said second element in a screwing direction when a torque applied to the attachment device exceeds a predetermined screwing torque threshold and to allow relative rotation of said stop member and said second element in an unscrewing direction when an unscrewing torque applied to the attachment device exceeds a predetermined unscrewing torque threshold.