Patent GB-1450397-A (GB)
Title: Safes
IPC: E05B65/00
Filed: 1973-01-22
Abstract: 1450397 Safety mechanism P THORNE & SON (SAFES & SECURITY SYSTEMS) Ltd 15 Jan 1974 [22 Jan 1973 26 March 1973] 3246/73 and 14464/73 Heading E2X A safe for valuables has a dye release mechanism and a safety mechanism comprising a frangible element 42 arranged so as to be fracturable by the shock of an attack on a lock of the safe or dye container or an attempt to open the safe by explosives, the frangible element 42 being further arranged normally to maintain the dye release mechanism in a non-released condition in the absence of any attack on the safe so that, on fracture of the element 42, the dye release mechanism is triggered and dye is applied to the contents of the safe. As shown in Figs. 1, 2 of provisional Specification 324673 a strong safe 10 with a hinged door 14 and a conventional lock 18 with bolts, not shown, has a plurality of auxiliary safety bolts 22 each slidably mounted in a housing 24 in the edge of the door and urged by a spring 26 towards a blind bore 28 in the fixed surround 12 in which position a ball-catch 34, 38 engages in a recess 40 to prevent withdrawal of the bolt. Each bolt has a stem 30 connected by a cord 32 to a safety mechanism comprising a frangible plate 42, made e.g. of glass and mounted between the door 14 and the conventional lock 18. The glass element 42 breaks when an attempt is made to drill out the lock 18 the cords 32 being released so that the bolts 22 advance into their locking positions. The cord 32 of one bolt, Fig. 2, passes round a pulley 46 at the end of the bolt stem 30 and is connected,-at one end, to a second safety mechanism comprising a thermally-responsive device 48 which melts at a predetermined temperature and releases the cord. Other bolts may be so connected. A cannister 50, containing dye under pressure and mounted on the door, is connected by a chain 52 to the stem 30 carrying the pulley 46 so that when this bolt is released by either of the safety mechanisms the chain 52 is pulled and the dye is released into contact with the safe contents. As shown in Fig. 1, of the provisional specification 1446473, a cannister 50 is mounted in a flanged channel-shaped support 54 which is slidably nested in a similar support 58 glued to a frangible plate 64, e.g. of glass, secured to the safe door panel 66. Bolts 70 pass through the flanges 56, 60 of the supports 54, 58 respectively, the plate 64, and into the door. A spring 68 tends to urge the cannister upwardly relative to the channel support 58. When the plate 64 is fractured the dye is released and, if an attempt is first made to drill out the bolts 70 so that the cannister can move freely when the plate 64 is subsequently fractured, the removal of the bolts 70 allows the spring 68 to move the cannister in the direction of the arrow and trigger the dye and release mechanism. In a further modification, Fig. 2 not shown, the cannister (50) is glued directly to the frangible plate (64) and a compression spring (76) is located around the chain (52) between the cannister (50) and the corresponding pulley of the stem of the safety bolt. If desired the frangible plate (64) can extend over the whole of the door and, before being anchored at (74), the cord (32) may pass through several holes (72) in the plate.