GB1151562A - Improvements in or relating to Fasteners - Google Patents

Abstract

1,151,562. Bolt fastenings. S. H. RUTHERFORD. 7 July, 1966 [12 April, 1965], No. 15553/65. Heading E2A. A bolt comprises a base I with means 4 for locating and guiding a movable bar 5, the bar being provided with a fulcrum at its leading end portion whereby the bar can function as a lever, and operating means whereby the bar can be moved to engage its leading end portion in a socket and can subsequently be rotated about the fulcrum, the operating means comprising two levers 6, 9 and a link 8 a first of the levers 6 being pivoted on the base and having the bar pivoted thereto, the link being pivoted to the first lever and to the second lever, the arrangement being such that on a first movement of the second lever 9 the bar is caused to move mainly longitudinally and on a second movement of the second lever the bar is caused mainly to rotate, the second movement terminating in an over-centre acion locking the bar in position. In the construction shown in Fig. 1 the lever 9 is pivoted to a bearing lug 3 attached to or formed integrally with the base, and the lever 6 is a bell crank lever which is pivoted to a lug 2 attached to or formed integrally with the base and to which the bar 5 is pivoted; the link 8 and lever 9 constitute a toggle the pivot 20 between the lever 9 and link 8 passing across the line joining the pivots 19 and 22 so that the bar is held in the position in which it is in engagement with the socket. The bar pivots on a heel 24 formed by tapering the end portions 23 of the bar. The pivoting draws the door 11 to which the bar is attached firmly into engagement with an abutment 13 of a fixed structure 12 to which the socket 7 is attached. A spring pad 10 is attached to the base 1 and bears on the lever 9 when the bar is in the disengaged condition thus preventing the lever 9 from rattling. In a modification the heel is formed by 'bending the bar instead of tapering its end portion. In a further modification the pivot 18 by which the bell crank lever is connected to the lug 2 is arranged to be above the pivots 21 and 22 and in this arrangement the bar 5 instead of having a heel which contacts the base which acts as a fulcrum about which the pivoting takes place, pivots about an upper bar of the guide 4. In a still further modification the lug 3 is placed between the lug 2 and to the guide 4 and the toggle mechanism is suitably rearranged. The link 8 can be longer than that shown and the lug 3 can be on a separate member instead of on the base 1. In an arrangement for moving two bars 5 in opposite directions the bars being at the top and bottom of a door, the two levers 9 are modified to form bell crank levers and they are both connected to a yoke 15 which is slidable on a plate 25, the yoke being moved by a pivoted panic bar (not shown) a portion of which engages in a hole 26 in the yoke 15. 'The construction shown in Fig. 1 can be modified by providing the base with a pair of lugs having holes through which a padlock can be passed to prevent the initial pivoting of the bolt which takes place upon release so that the bolt cannot be released without undoing the padlock. The mechanism can be enclosed by a cover attached to the base 1 and the cover can be provided with holes through which a padlock can be passed to prevent release. In a further construction the lever 9 is pivoted so that it moves parallel to the base 1 and a universal joint is incorporated in the link 8 to permit this. An arrangement is also described which is stated to be suitable for a vehicle door in which the lever 9 is spring loaded so that it tends to move the bar 5 into the socket a pawl being provided which engages a notch associated with the lever 9 when the bar 5 is partially withdrawn by operation of a handle connected to the lever 9 when the door is opened and which holds the bar 5 retracted; a'spring loaded plunger is mounted on the door in such a manner that it contacts the abutment 13 before the door is fully closed to release the pawl to enable the spring to engage the bar with the socket.