Equipment security locking device

Claim 1

A protective locking device for rendering inaccessible the head of a bolt having a head and a threaded shank which is adapted to protrude from the locking device through a Mounting body and into an equipment to be protected, said locking device comprising: a base member adapted to abut the body, said base member having a hole through which the shank of the bolt passes and protrudes and a seat at the hole preventing the bolt head from passing through the hole; a protective member having an end member positioned to be juxtaposed to, and cover, a portion of the base member around the seat and having through said end member, a threaded hole which communicates with the bolt head; said protective member having a hollow shank with a peripheral wall which extends in a direction away from said seat; said peripheral wall having spline means attached to its inner surface, extending in a direction away from said seat; a lock body having a barrel adapted to fit into said shank and having a threaded neck which engages said threaded hole when the barrel is inserted into the shank; said barrel containing transverse groove means and locking blade means movable transversely through said groove means; means resiliently urging said blade means to protrude from a side of the barrel so as to normally engage said spline means; said barrel having a key slot configured to permit entry of a key in the axial direction, to engage and urge said blade means to withdrawn from engagement with the spline means so that the barrel may be rotated to disengage its neck from the threaded hole so that the lock body may be removed from the shank, thereby permitting access to the bolt head; and a shielding envelope extending from the end of the hollow shank remote from the base member to a periphery adapted to abut the base member at a position outside of said seat and to envelope the circumference of the lock barrel and the seat; and means attaching the envelope to the base so that the envelope cannot be removed from the base without withdrawing the blade means from the splines by means of the key, whereby when the shank of the bolt protruding from the base is covered by the body and equipment the locking device cannot be removed from the body and access to the bolt head is prevented while the locking blade means are in engagement with the spline means.