Antique Yale Safe Lock

its a 'reverse alarm clock' sort of.. you set the time you want it to 'open' and when the clock runs down to that point, it allowed external mechanism in the safe to be moved to the open position and the door then could be opened up. there is NO, as far as you are thinking, unlocking it, externally from the outside of the safe once set and the door locked, you rely on the clockwork mechanism to 'run down' and do its job.

there are 2 clocks as a fail safe, EITHER by itself will allow, one the time that was set has passed and the mechanism moved its internal mechanism, the external stuff to be moved. 2 was used in case one malfunctioned. later ones used 3 in some cases.

market value? whatever a collector thinks its worth.

--Shiva--

able to 'run down' a time lock to zero to help his escape. The time lock must have either been accessible from the inside or sufficient tools / keys kept inside for such an emergency.

I read of a new vault being equipped with a telephone, emergency generator, food and water to enable an employee to survive for 72 hours (presumably the maximum set time for a timelock (I think that they are more like an egg timer than an alarm clock)).

In another case I remember some robbers dialled up the full 72 hours and locked the vault door behind them - the bank could not fully assess what had been taken until 3 days later.

NEW vault's are not as air tight as the old Pressure doors.. but they have communication means usually to boot, just for that reason. and I have seen 144 hour locks. and you are correct, egg timer could be better.. the idea is when it 'runs down', mechanism IS moved, allowing the actual safe door bolt work to be moved to open position, assuming you know the combo/s

--Shiva--