NZ201399A - Locking mechanism for door of security enclosure - Google Patents

Description

2 013 9 9 Priority Datfefs): . ^ ■ &'.?l Cotnpktff C c-soification Filed: 37."7,'& d«K e.qf 6 Eps;c iJob-tostfk 2 8 FEB 19R5 P.O. Journal f:Ie: iiaataciia*1 ;.%7. ;No.: Date: ;NEW ZEALAND PATENTS ACT, 1953 ;COMPLETE SPECIFICATION L~Oc(C""V^ vv> r\i -foC doo f ;°f SE^U^ITY ENCL0SURE# ;27 JUU982 ;DECEIVED ;CHUBB NEW ZEALAND LIMITED, a New Zealand Company, of 98-100 Dixon Street, Wellington, New Zealand, ;hereby declare the invention for which ^ / we pray that a patent may be granted to^i^/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - ;- 1 - ;2013^9 ;The present invention relates to safes, vaults, strongrooms, and the like security enclosures. ;It is customary for the doors of such enclosures to be locked by means of bolts thrown from the door into engagement with the surrounding frame or like structure, and in the more secure arrangements bolts are thrown from the door in at least two mutually-inclined (generally perpendicular) directions, as from two, three or all four edges of a rectangular door. ;It is an aim of the present invention to improve the resistance to certain forms of burglarious attack of a security enclosure door as indicated above, and accordingly in one aspect the invention resides in a locking mechanism for the door of a security enclosure comprising bolts arranged to be thrown from the door in at least two mutually-inclined directions and a driving mechanism arranged to throw and withdraw said bolts in their respective directions and at predetermined relative rates, and wherein portions of respective bolt structures which move in inclined directions are interengaged by coupling means arranged to block movement of the bolts into their withdrawn positions otherwise than by movement in their respective said directions and at said predetermined relative rates. ;Preferably said coupling means comprise a pin or the like member carried by one of the bolt structures and cooperating with a slot provided in another bolt structure. In the usual case where bolt structures are driven in orthogonal directions and at the same linear rate the slot will extend at <5° to the directions of movement of both structures, but differently inclined or otherwise configured slots can be provided as appropriate where two bolt structures are intended to move in other relative directions and/or at unequal rates. Preferably, for a purpose which will become apparent from the ensuing particular description, any such slot is also provided, .in the region of the slot normally occupied by the associated pin when the cooperating bolt structures are thrown, with short extensions arranged to permit a limited (but only a limited) ;201399 ;-3- ;withcirawing movement of one of the cooperating bolt structures in its respective direction without movement of the other bolt structure. ;The invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: ;Figure 1 is an elevation of the inside of a safe door incorporating a -locking mechanism in accordance with the invention, with the boltwork shown in its thrown condition; and ;Figure 2 shows a pin and slot coupling which forms part of the mechanism of Figure 1, in three different positions. ;Referring to Figure 1, a safe door 1 is equipped with four sets of bolts 2,3,4 and 5 arranged to be thrown from the four edges of the doer to engage in respective detentions in the associated door frame Cnot shown). The bolts in each set are connected together by respective straps 6-9 and each strap is driven via a respective drive rod 10 from a central throwing and isolation unit 11. The unit 11 includes mechanism arranged to drive the rods 10 in unison to throw or withdraw the bolts 2-5, all at equal linear rates, in response to the turning in a corresponding sense of a handle or wheel (not shown) accessible on the outside face of the door. Two locks 12 and 13 are provided which, ;when the main boltwork has been thrown, are operated to throw their own bolts into engagement with the adjacent drive rod 10 thereby to resist forced retraction of the main bolts 2-5. Furthermore, the unit 11 includes mechanism responsive to the throwing of the lock bolts to disengage the coupling of the external handle or wheel to the means which drives the rods 10 so that the handle or wheel cannot thereafter be used to put force on the boltwork. This disengagement mechanism is preferably of the typo disclosed in; ;New Zealand Patent Specification No. 199365. ;In accordanco with the present invention the adjacent pairs of orthogonally-moving bolts straps 6 and 7, 7 and 8, 8 and 9, 9 and 6, are interconnected not only via the rods 10 and associated driving mechanism, but also by respective pin and slot couplings 14/15. In the illustrated embodiment ;2013^9 ;-4- ;the two vertical-edge bolt straps 7 and 9 each have upper and lower tail plates 16 and 17 carrying the pins 14 which engage in respective slots ;15 provided in overlapping planar portions of the hotizontal-edge o ;bolt straps 6 and 8. Each slot 15 is inclined at 45 to each of the directions of movement of the respective cooperating bolt straps so that, in normal operation, as the boltwork. moves between its withdrawn and thrown conditions the pins 14 run from one end their respective slots 15 to the other, ie as. indicated by Figures 2A and 2B in the case of the coupling between bolt straps 8 and 9. At the end of each slot 15 at which the respective pin 14 is located in the thrown condition of the boltwork, the slot is provided with a pair of orthogonal side extensions 15A and 15B aligned with the directions of movement of the respective cooperating bolt straps, giving each slot an arrow-head formation. ;The purpose of the pin and slot couplings 14/15 is to provide the boltwork with still greater security against burglarious attack, particularly where this involves attempts at retraction of the bolts eg by use of explosives or other gross force. As will be appreciated, the angling of the slots 15 is such as to block retraction of the boltwork from its thrown to its fully-withdrawn condition except by the simultaneous and correctly-relative movement of the four bolt sets 2-5 in the manner provided by the driving mechanism (which in this condition is isolated from the external handle or wheel), and such movement would be extremely difficult to achieve by any forcing technique, even if the blocking action of the lock bolts could be overcome. The likely result of any attempt at forced retraction is that one or more pins 14 will become lodged in associated slot extensions 15A or 15B -for example, if sufficient force could be-applied to the lower-edge bolts 4 they might be retracted some way but this would only result in the bolt strap 8 moving so that the pin 14 carried by the tail plate 17 of bolt strap 9 now lies in the associated slot extension 153 (as shown in Figure 2C) and likewise for the pin 14 carried by the tail plate 17 of bolt strap 7. In this condition further retraction of the bolt strap 8 is blocked by reaction against the bolt straps 7 and 9, and any retraction ;2 01399 ;-5- ;of either bolt strap 7 or 9 would be blocked by reaction against the bolt strap 8. Furthermore, since the pins 14 are now misaligned from the main 45° angled portions of the slots 15 bolt retraction could not take place even if the isolating function of the unit 11 were subsequently overcome and the driving mechanism operated. In other words, the pin and slot couplings 14/15 ensure that bolt retraction can only be effected by the predetermined, synchronised movement which is normally provided by the driving mechanism, and furthermore that any forced deviation from that movement will only serve to increase the difficulty of further bolt retraction. *

Claims (6)

201399 -6-; What we claim is:

1. A locking mechanism for the door of a security enclosure comprising bolts arranged to be thrown from the door in at least two mutually-inclined directions and a driving mechanism arranged to throw and withdraw said bolts in their respective directions and at predetermined relative rates, and wherein portions of respective bolt structures which move in inclined directions are interengaged by coupling means arranged to block movement of the bolts into their withdrawn positions otherwise than by movement in their respective said directions and at said predetermined relative rates.

2. A mechanism according to claim 1 wherein a said coupling is adapted to permit limited withdrawing movement of either bolt structure coupled thereby in its respective said direction without corresponding movement of the other such structure, and thereafter to block further withdrawing movement of both said structures in their respective said directions at any relative rate.

3. A mechanism according to claim 1 or claim 2 wherein a said coupling comprises a projection carried by one bolt structure cooperating with a slot provided in an adjacent bolt structure.

4. A mechanism according to claims 2 and 3 wherein a said slot comprises,in the region of the slot normally occupied by the cooperating projection when the two bolt structures are thrown, short extensions aligned with the respective directions of withdrawing movement of said structures. 2 013 9 -7-

5. A locking mechanism for the door of a security enclosure substantially as hereinbefore described with reference to the accompanying drawings.

6. A security enclosure having a door equipped with a locking mechanism in accordance with any preceding claim. (\&Q.\..<^c\cLcJ /-4A ^ t"fgcJ BrfC/Their aut^Sd Agents, A- J. PARK & SON SI Per ^ 7