GB1056525A - Bolts - Google Patents

Abstract

1,056,525. Bolt fastenings. ALBERT MARSTON & CO. Ltd. and H. M. WILLIAMS. March 17, 1965 [March 17, 1964], No. 11138/ 64. Heading E2A. A mortise bolt for doors intended to be used in an emergency comprises a casing 10 a bolt member 24 mounted on a bolt carrier 14 resilient means e.g. springs 22, 23 urging the bolt carrier towards a door releasing position and a frangible body 28 holding the bolt carrier in the door bolting position so that upon breaking the body the bolt carrier is moved to its door releasing position, the arrangement being such that access can be had to the frangible body from both sides of the casing. In the construction shown the bolt carrier is formed with a shelf 32 upon which the forward edge of the frangible body 28, which as shown, is a plate of glass, rests. The rearward edge portion of the plate of glass rests upon an upstanding flange 31 of the casing and lips 30 prevent movement of the plate longitudinally away from the bolt carrier. A cover plate for the casing is provided with protrusions which maintain the plate 28 in the required position, both the cover plate and the casing having apertures through which access to the plate 28 is obtainable so that it can be broken. The bolt carrier is guided in its movement by bars 20 and 21 which project rearwardly from a front plate 11 of the casing and these guide bars are surrounded by the springs 22 and 23 which are under compression when the plate 28 is in position so that when it is broken the springs urge the bolt carrier rearwardly and move the bolt member 24 to the door releasing position. The bolt member 24 is attached to the bolt carrier by means of a stem 25 slidable in a slot 26 in the carrier, a coil spring 29 being located around the stem 25 and acting between the rear face of the bolt member and the front face of the carrier 14, this construction enabling the bolt to be retracted by closing the door after the plate 28 has been fitted. Instead of the plate 28 being made of glass it can be made of earthenware and can carry an instructive or identifying legend. The extension 17 is provided with a protrusion which extends to the side of the casing to form a shelf on which the plate 28 may be located if desired. A shelf is also formed at the opening through the casing so that the frangible body may be located on the shelves. When the shelves 32, 33 are used a frame for the hole in the door by which the frangible body is reached is provided to prevent the inadvertent or unauthorized removal of the body. Reference has been directed by the Comptroller to Specification 943,249.