GB251754A - Improvements in locking or security devices for pins, studs, shackle bolts and the like - Google Patents

Abstract

251,754. Thomas, R. E., and Billetop, T. C. April 16, 1925. Locking bolts, studs, and set-screws.-A pivoted member D accommodated wholly in a slot in the bolt during the insertion of the latter, falls over under the action of gravity or a spring to prevent the withdrawal of the bolt, As shown in Fig. 1 the locking member is cut away so as to be unbalanced with reference to its pivot d' and may be withdrawn into alignment with the bolt by a cord E passing through a channel a<4> and ending in a ring e<1>. In one modification the bolt is threaded adjoining its head and after the cottar D has fallen over a nut on the threaded portion withdraws the bolt sufficiently to prevent the return of the cottar into alignment with the bolt. The bolt may be non- circular or its head may be formed with one or more flats to ensure that the pivot of the bolt is maintained in the required position. In another modification, Fig. 6, the cottar D<1> is V-shaped: its movement is limited by the projection a<8> and it may be lifted out of locking position by a removable key E<1>. In another form for use with a non-circular bolt, the cottar, of similar crosssection to the bolt, is pivoted to the end thereof by a pin or stud coaxial to the bolt. The cottar may be fitted within a recess in the side of the bolt instead of in a slot penetrating completely through it. The locking member may also consist of a ring which is prevented from falling out altogether by a pin fixed in the bolt.