concept for two key lock

[raimundo]

I had this idea for a two key lock with one keyway, could be used like safe deposit lock, or any other app where two persons were the prefered trust circle to open the lock, it would be a medeco or similiar high security lock with two 'bibles' with one being five pin and the other being six pin, to unlock the first key would go in and turn the core a part of the way, but the five pin key could not pass the six pin 'bible' it would stop and be removed, then the six pin key would be inserted and the lock unlocked,
in this way, someone could leave a key on the premises and carry the other key, or trust could be devided among two people, or one person could unlock at the beginning of the day and leave it in what a combination lock would be refered to as 'day combination'
think of other situations in which this would be useful,
also, if medeco type mechanism were used, two sidebars would also be used, and each different.
just throwing that out for discussion.

[n2oah]

Good job, raimundo. Your post is the 666th post in this forum. You are doomed forever

[TorchBlower]

my work uses a two key system for the safe; one on every manager and one on the Brinks truck guy. I don't know if it's any close to what you're describing but it's something

[Chrispy]

The safety box system at work uses two lever locks to open a box. The control key must be inserted and turned before the box key is inserted and turned. The locks are probably between 7 and 10 levers per lock.

[Chucklz]

If a medeco like system isn't used, wouldnt this just be a master/slave system, in which case the slave key can only turn a limited distance... perhaps activating some kind of electrical switch, while the master key would be able to turn the full rotation?

[SFGOON]

The first position has five drivers, the second has six. For the first key, the sixth pin just hangs loose, not being activated until the plug reaches the second bible, where it is activated by the corresponding driver, stopping the motion of the lock.

Very nice - could it be defeated by a conventional plug spinner?

[hzatorsk]

Very nice - could it be defeated by a conventional plug spinner?

I was thinking the same thing.

Then again... It also seems if the key turned far enough the sixth pin would lock the plug requiring the other key to advance further... the five key wouldn't be able to turn the plug back to locked.

You'd almost need some sort of slot in the plug that allows the sixth pin to not interfere with the first 90 degrees of rotation.

Perhaps a concentric dual plug (similar to a master ring) would achieve the goal?!?

Z

[raimundo]

yep, a plug spinner attached to that first key, unless the lock is fitted with stronger springs on that 6 pin, or perhaps someone else has an idea of how it could be designed to keep the spinner from working, its not a finished idea, I was just proposing it for discussion and improvement. Thanks for the point out goon.

[SFGOON]

But what if the plug HAD to stop at the second bible? One could make the second bible not line up with the first, making it so you had to "shift" the plug to get to the next set of drivers. That would effectively defeat plug spinners.

[hung82000]

Would it be possible to require the lock to be pressed in or pulled out somehow after the first key was used?

[SFGOON]

Exactly what I was thinking.

[hung82000]

Sorry, I didn't realize I was stealing your idea. We have a couple of safes where you must pull the knob out before turning to the next digit. I wonder how feasible something like that would be on a lock.

[SFGOON]

I'm thinking the plug could have grooves for the drivers to facilitate "shifting" the plug. Can anyone think of a way this would cause a security issue?

[hzatorsk]

duuh... yeah... a plug that can be pulled out or turned to the next position has a built in tension wrench. ITSELF!!!

You are making this thing easier to open. Not harder.

[SFGOON]

Duuh, not if you had to shift it with the key