Patent GB-1250373-A (GB)
IPC: E05B9/08
Filed: 1969-06-19
Abstract: 1,250,373. Locks. BAUER A.G. 19 June, 1969 [21 June, 1968], No. 31120/69. Heading E2A. A safety deposit box has a door 22 to the rear wall of which a lock is releasably fastened, the fastening means consisting of headed studs 23 carried by the rear wall of the door which in the fastening position engage key hole slots 24 in the rear cover plate 2 which closes the lock housing 1; protruding from the lock housing is a bolt 3 which in the bolting position engages a frame of the box and which is slidable to releasing position, the bolt being operated by a renter's key which also moves tumblers which normally prevent movement of the bolt, the bolt also being held in the bolting position by a pivoted detent 10 which is moved to release the bolt by a second key, the housing being held on the door in the operative position in which the studs are in engagement with the narrow part of the key hole slots, by a detent 33 which engages apertures in the cover plate and the door and which is released by a third key so that the lock can be moved parallel to the door to release the studs from the key hole slots. In the construction shown the lock has a single key hole for receiving any of the keys and to move the bolt to releasing position, in normal operation, the second key must first be inserted in the key hole and turned; the initial part of the rotation of the key moves the tumblers 8 to positions which are different from the positions which they take up when moved by the renter's key so that tabs 30 are moved out of the path of projections 29 of a slide 27 so that further rotation of the key can move the slide. The bolt is not moved since the tumblers still prevent its movement. The rear edge of the slide has a flange 31 which engages and rotates a member 15 which in turn rotates the detent 10 to a position in which it no longer prevents movement of the bolt. The second key is then removed from the lock leaving the slide in the position in which it is holding the member 15 and thus the detent 10 in the releasing position and the renter's key is then inserted into the lock and rotated; the initial part of the rotation moves the tumblers to. positions in which a gate slot of each is aligned with a projection 9 on the bolt, the subsequent movement sliding the bolt to the releasing position. The bolt is moved to the bolting position by reverse movement of the renter's key and the second key is used to move the detent 10. The third key for removing the lock from the door is similar to the second key and differs only in that the key is in two parts so that the handle can be removed leaving the bit end portion of the lock; when this key is inserted into the lock and rotated it moves the tumblers and the slide in exactly the same way as the second key and the slide allows the detent 33 to move out of the aperture in the door under the urge of a spring 36 since the detent 33 is held in the aperture when the slide is in its normal position by engagement with an inclined face 32 of the slide; this also happens when the second key is inserted into the lock and turned but in such a case the second key protrudes through the door and prevents movement of the lock on the door; when the third key is used however and its head end portion is removed the remainder of the key does not protrude through the key hole in the door and consequently a tool can be inserted into the key hole to move the lock so that the headed studs become disengaged from the key hole slots. In a modification the lock contains a solenoid, the armature of which is connected to the member 15 so that energising the solenoid causes the member 15 to rotate which in turn moves the bolt holding detent 10 so that with this modification the use of the second key is not required since once the solenoid is energised the renter's key can be used to move the bolt. However the construction of the lock is such that the second key can be used as an alternative to the use of the solenoid.