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Re: Friction-Fence Locks

PostPosted: Fri Mar 12, 2021 5:40 pm
by MartinHewitt
A bit more information about the CNAB-6.

This one shows nicely the friction fence mechanism. I colored blue, what would be the drive cam in a real friction fence lock. It has moved away from the spindle and drives only the friction fence. The friction is happening at the red location driving the big part. This big part is then connected to the part which has the actual fence, which I have marked pink.

fig4.jpg


The part marked in red is basically the "software" of the lock. The cogs on this barrel control which wheel is moved. It is interfacing with the cogs on the primary gear stack (green). The program counter is incremented by the blue hook.

fig20.jpg


This figure shows the two gear stacks. The connection between them determines the combination. The missing cog (pink) on the secondary gears are the gates. The part marked in green is rewinding the program barrel to the start.

fig9.jpg


There is are also mechanisms to turn the primary gear stack back, to change the combination and to lock and unlock the back cover.

It is quite difficult to show the operation, because the primary gear stack is fixed to the T plate which covers a lot of the lock's mechanics. I made a few videos showing an opening with details hoping, that it helps understanding the lock. I think with the help of the above figures it is possible to understand what is shown in the videos.

https://vimeo.com/521935515
https://vimeo.com/521935609
https://vimeo.com/521935676
https://vimeo.com/521935750

Re: Friction-Fence Locks

PostPosted: Fri Mar 12, 2021 8:39 pm
by madsamurai
wow, that's a piece of work... looks more like a clock mechanism. Nice work on the videos. So does the dial spring back to zero after setting each digit? It looks like it all turns the same direction...

Re: Friction-Fence Locks

PostPosted: Sat Mar 13, 2021 2:38 am
by MartinHewitt

Re: Friction-Fence Locks

PostPosted: Sun Oct 31, 2021 2:45 pm
by MartinHewitt
Anyone seen the non-S&G lock used in Kumahira fire safes? It looks like a friction fence lock with a zamak case.