Info from http://www.britishtelephones.com
"Used in all public Coin Collecting boxes prior to the introduction of the electronic payphones around 1988.Fitted to the cash box compartment cover and differing keys were allocated to each lock.
These are tough locks, liable to break a drill bit."
There is a rather indistinct picture that shows an oval bowed key.
An extract from 1966 instructions from the same site
"To effectively destroy locks and keys it is essential that the levers, tumblers or key steps are mutilated so that their dimensions cannot be used to construct keys. Dispose of keys and lock levers as follows. Dispose of all other parts as scrap metal.
To destroy a Lock No. 6M or No. 15… dismantle the lock and remove the levers. Dispose of the levers in a solid-fuel furnace, if available, or after thoroughly mutilating them, dispose of them as rubbish.
To destroy a Lock No. 14… dismantle the lock and using a hammer and suitable drift, drive the cylinder out of the barrel from the rear. Alternatively, clamp the lock in a vice and drill a hole in the barrel as described in par. 16.
To destroy keys dispose of them in a solid-fuel furnace or clamp them in a vice and mutilate the stepped part, using a hammer and cold chisel, then dispose of them as rubbish"
Seems my memory was faulty about the method of destruction but they seemed pretty determined to keep them out of the wrong hands….
////(oldlock) Seems odd to have exposed screws, is the lock cap somehow secured when the lock is in-situ ?////
I think that the lock slid into a pocket inside the box, I remember that the door on the front of the box was a piece of ¼ inch plate that dropped into a slot and there was no keyhole in the plate. The keyhole must have been under or on the side of the box.
////(mercurial) I can’t see any false notches/serrations on your lock’s levers////
There are false notches on all of the levers, they are very shallow (just visible when holding the lock)
////my lock is constructed such that the bolt cannot be thrown unless at least one lever is lifted quite high, moving a block of metal (just like the block of metal attached to the spring in your lock - but I can’t see how this mechanism would block bolt movement in your lock.)////
This one is similar, there is a projection on the side of the bolt (not easily seen in the pictures) that is obstructed by the sprung block. Three of the levers touch the block when unlocked. The key is retained while unlocked.
If you click on the picture with the case you can see the projection mentioned above.
////I remembered that my lock has a post for the key////
Seeing this, I took a good look in case mine had lost its post! it is apparent that it was made as it is.
