EP0018712B1

EP0018712B1 - Bolt mechanism, and security enclosure having such a bolt mechanism

Info

Publication number: EP0018712B1
Application number: EP19800300830
Authority: EP
Inventors: George William Dyson; Charles Frederick Laxon
Original assignee: Chubb and Sons Lock and Safe Co Ltd
Current assignee: Gunnebo UK Ltd
Priority date: 1979-03-23
Filing date: 1980-03-19
Publication date: 1983-01-12
Also published as: DE3061569D1; EP0018712A1

Description

The present invention relates to bolt mechanisms, and more particularly is concerned with bolt mechanisms for safes, vaults, strongrooms and the like security enclosures.
A known form of bolt mechanism for the door of a safe or the like enclosure comprises a handle or like manually operable member accessible from without the enclosure, and a crank arm rotatable in either sense by the manually operable member, the crank arm being engageable with a drive slot in a linearly moveable transmission member operatively associated with the boltwork of the door whereby rotation of the crank arm in either sense by the manually operable member imparts linear motion to said transmission member in a corresponding sense to throw or withdraw the boltwork. One or more locks are also provided for selectively locking the boltwork when in its thrown condition. The handle or like member of this mechanism is liable to be used in an attack on the enclosure to put force on the boltwork and, specifically, there is the disadvantage that force can be applied through that member in the sense to withdraw the boltwork against the action of the locking mechanism.
In order to overcome the above disadvantage it is also known to provide a mechanism for selectively disengaging the coupling of the manually operable member to the boltwork when the latter is in its thrown condition whereby force cannot then be transmitted from said member to the boltwork such as to withdraw the boltwork from that condition. Such is disclosed in United Kingdom Patent Specification No. 936155 where the lineariy moveable transmission member is split into two parts which can be engaged and disengaged by the perpendicular movement of a U-shaped coupling block adapted to engage in slots provided in each part of the transmission member. The coupling block is supported by a platform in which it can slide together with the two parts of the transmission member while the latter remain engaged, the platform and block being carried by the bolt of a lock for selectively locking the main boltwork when in its thrown condition. This arrangement requires the accurate alignment of three elements (the block and two parts of the transmission member) before the lock can be unlocked and the coupling re-engaged after disengagement has taken place. The sliding block also adds to the weight and friction of the transmission member which must be shifted each time the door is opened and closed, and the block and platform adds significantly to the weight of the lock bolt.
The present invention is concerned to provide a solution to the same problem as that to which the mechanism of the said specification is directed, but in a manner which avoids the split transmission member and sliding coupling of that mechanism. This problem is solved by a bolt mechanism according to claim 1 which is characterised in that said disengaging means are operable to disengage said crank arm from said drive slot.
Preferably the disengaging means are operatively associated with a said lock for selectively locking the boltwork when in its thrown condition, whereby operation of the lock acts to disengage the crank arm from the drive slot as aforesaid. This need not necessarily be the case, however, and it is also possible, for example, for the disengaging means to be embodied as an independent key or combination operated mechanism, separate from any such lock.
The disengagement of the crank arm from the drive slot may be effected by a movement of the crank arm in a direction transverse to the rotational axis thereof, in which case the crank arm may be provided with a slot within which is received a flat-sided rotary drive member operatively associated with the manually operable member, thereby to permit both the transmission of rotary motion from the drive member to the crank arm upon manipulation of the manually operable member and motion of the crank arm relative to the drive member in a said transverse direction upon operation of the disengaging means.
The invention also provides, per se, a safe, vault, strongroom or the like security enclosure of which the door comprises a bolt mechanism in accordance with the foregoing.
These and other features of the invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 illustrates a bolt mechanism in accordance with the invention installed within a safe door; being shown in the condition which pertains when the safe bolts are withdrawn;
Figure 2 illustrates the mechanism of Figure 1 in the condition which pertains when the safe bolts are thrown and the lock operated;
Figure 3 illustrates a modification to the mechanism of Figures 1 and 2, being shown in the condition which pertains when the safe bolts are-withdrawn; and
Figure 4 illustrates the mechanism of Figure 3 in the condition which pertains when the safe bolts are thrown and the lock operated.

Referring to Figure 1, a handle (not shown) is mounted externally of the door 1 and has a spindle 2 that extends through the door to be coupled to a crank arm 3. More particularly the spindle 2 extends into a slot 4 in the arm 3 and is there fitted with a bush 5 that has flats 5A which contact with the opposite walls 6 of the slot 4. The arm 3 accordingly turns with the spindle 2 under torque applied to the handle, but can slide transversely with respect to the rotational axis of the spindle 2.
The arm 3 carries a crank pin 7 to engage in a drive slot 8 of a scotch-yoke coupling to a connecting bar 9. The connecting bar is mounted to slide longitudinally and is coupled to a strap 10 that carries the safe bolts 11 (only one of which is shown in part). Turning of the spindle 2 accordingly turns the crank arm 3 and moves the pin 7 up or down the slot 8. This movement of the pin 7 drives the bar 9 to and fro and thereby throws the bolts 11 or withdraws them in dependence upon the sense in which the external handle is rotated.
Referring now to Figure 2, when the bolts 11 have been thrown into engagement with the body of the safe they are locked there in the normal manner by key-operation of a lock 12, the bolt 13 of the lock being thrown to engage in a notch 14 in the bar 9. Such operation in this case, however, also serves to disengage the coupling of the crank pin 7, and hence also of the external handle, to the boltwork in the bolt- withdrawing sense. To this end a plate 15 is connected to the lock bolt 13, and lies between the arm 3 and the connecting bar 9. This plate has an arcuate slot 16 into which the crank pin 7 extends and along which the pin runs during its normal operation when, throwing the safe bolts 11. When the bolts have been thrown but before the lock 1.2 has been operated the crank pin is in the position indicated in broken line in Figure 2. When the lock is then operated, however, the plate 15 moves with the lock bolt 13 to carry the pin 7,. engaged in slot 16, to the position indicated in full line in Figure 2, the arm 3 sliding on the spindle bush 5 to permit this operation. In this condition the rotary connection between the spindle 2 and arm 3 is still effective but, as will be appreciated from the Figure, the crank pin 7 is now isolated from the flank 8A of the drive slot 8 so force cannot be applied to the connecting bar 9 via the spindle in the sense to withdraw the safe bolts 11.
Preferably, provision is also made in the mechanism for blocking rotational movement of the crank pin in this disengaged condition, such as by the inclusion of a fixed locking block 17 which lies in the path of the pin (but being offset from the arm 3, plate 15 and bar 9). Also, if the opposing flank 8B of the drive slot 8 is extended in comparison with flank 8A, as shown in the Figure, so that the pin 7 does not become isolated from this longer flank, the blocking of the rotational movement of the pin will provide an additional positive locking action against the withdrawal of the safe bolts.
The unlocking operation of the lock 12 withdraws the bolt 13 and plate 15 so that the pin 7, still engaged in the slot 16, is pulled towards the spindle 2 with the arm 3 sliding on the bush. 5, to re-establish' coupling with the drive slot flank 8A. Turning of the external handle in the appropriate sense will therefore now be effective to withdraw the safe bolts 11.
It will be noted that a longitudinal slot 18 is provided in the plate 15 to clear the bush 5 as the plate moves to and fro with the lock bolt 13, and similarly a longitudinal slot 19 is provided in the connecting bar 9 to clear the spindle 2 during its to and fro movement as the safe bolts are thrown and withdrawn.
A modification to the mechanism is illustrated in Figures 3 and 4. In this there is an arm 9¹, pin 7', plate 15' and slot 16' equivalent to the components identified by the same unprimed reference numerals in Figures 1 and 2. In this case also there is a flat-sided spindle 2' (or an equivalent bush) which engages between the flats 6' of a slot 4' in the arm 3' to drive the latter in rotation when the safe bolts are thrown or withdrawn, but the throw of the lock bolt to which the plate 15' is connected is such that when the plate is moved on operation of the lock the crank pin and arm are carried down into a position in which the spindle 2' lies in an end 4A' of the slot 4' which is opened out to a diameter not less than the greatest cross- sectional dimension of the spindle. Consequently, in this condition the spindle and the external handle to which it is connected can rotate without restraint, the thus free wheeling handle now being completely isolated from the rest of the bolt-throwing mechanism. Only when the spindle is correctly aligned by the external handle will it be possible to unlock the safe bolts, raising the plate 15' and crank arm 3' so that the spindle re-engages between the flats 6'. The handle-isolating action of this mechanism may be provided as an addition to the above-described isolation of the crank pin from its driving slot in the connecting bar.

Claims

1. A bolt mechanism for the door (1) of a security enclosure comprising a manually operable member accessible from without the enclosure, a crank arm (3; 3') rotatable in either sense by the manually operable member and operatively connectable with a drive slot (8) in a linearly moveable transmission member (9) operatively associated with the boltwork (10, 11) of the door whereby rotation of the crank arm in either sense by the manually operable member imparts linear motion to said transmission member in a corresponding sense to throw or withdraw the boltwork, a lock (12) for selectively locking the boltwork (10, 11) when in its thrown condition, and means (15; 15') for selectively disengaging the coupling of the manually operable member to the boltwork when the boltwork is in its thrown condition, at least in the sense of force transmision from said member to the boltwork such as to withdraw the boltwork; characterised in that said disengaging means (15; 15') are operable to disengage said crank arm (3; 3') from said drive slot (8).

2. A mechanism according to Claim 1, wherein said disengaging means- (15; 15') are operatively associated with said lock (12) whereby operation of the lock acts to disengage the crank arm (3; 3') from the drive slot (8) as aforesaid.

3. A mechanism according to Claim 1 or Claim 2, wherein the disengagement of the crank arm (3; 3') from the drive slot (8) is effected by a movement of the crank arm (3; 3') in a direction transverse to the rotational axis thereof.

4. A mechanism according to Claim 3, wherein said crank arm (3; 3') is provided with a slot (4; 4') within which is received a fiat-sided rotary drive member (5; 2') operatively associated with the manually operable member, thereby to permit both the transmission of rotary motion from the drive member to the crank arm upon manipulation of the manually operable member and motion of the crank arm relative to the drive member in a direction transverse to the rotational axis thereof upon operation of said disengaging means (15; 15').

5. A mechanism according to Claim 3 or Claim 4, wherein the crank arm (3; 3') is arranged to engage with the drive slot (8) through the agency of a crank pin (7; 7') carried by the arm and said disengaging means comprise a linearly moveable disengaging member (15:15') provided with an arcuate slot (16; 16') into which the crank pin extends and along which the crank pin runs when the crank arm is rotated to throw or withdraw the boltwork (10, 11), but whereby movement of said disengaging member acts to disengage the crank pin from the drive slot (8).

6. A mechanism according to any one of Claims 1 to 5 comprising means (17) for blocking rotational movement of the crank arm (3; 3') when disengaged from the drive slot (8).

7. A mechanism according to any one of Claims 1 to 6, wherein said disengaging means (15; 15') are operable to disengage the crank arm (3; 3') from that flank (8A) of the drive slot (8) which is effective in the transmission of force from the arm to said transmission member (9) such as to withdraw the boltwork (10, 11), but not from the opposing flank (88).

8. A mechanism according to any one of Claims 1 to 7, wherein said disengaging means (15') are further effective to disengage the crank arm (3') from a rotary drive member (2') operatively associated with the manually operable member and arranged normally to transmit rotary motion in either sense from the manually operable member to the crank arm, to the extent of preventing such transmission of rotary motion.

9. A mechanism according to Claim 8, wherein said disengagement of the crank arm (3') from the rotary drive member (2') is effected by a movement of the crank arm in a direction transverse to the rotational axis thereof.

10. A mechanism according to Claim 9, wherein the rotary drive member (2') has a pair of opposed flat sides and is received within a slot (4') in the crank arm (3'); said slot has a first portion with sides (6') complementary to the flat sides of the drive member and an adjoining second portion (4A') of a cross-section to permit the drive member to rotate freely therein; and said disengaging means (15') are operable to move the crank arm from a position in which the drive member lies within said first portion of its slot to a position in which the drive member lies within said second portion thereof.

11. A security enclosure with a door (1) characterised by a bolt mechanism in accordance with any preceding claim.