Prison locks
http://rapidshare.com/files/125852450/P ... s.rar.html
The only reason I was able to get these pictures is because I had to take a lock out of the center and to my shop to make a new combination and keys.
These are multiple throw locks, designed to have 4 actions.
1 is completely retained, but the spring tention on the little button, when depressed (by the door frame) causes the lock to engage to 2.
2 is activated when the door is shut, but not locked down. The door cannot be opened at this point, but it is evident that the door has not been locked to 3 by a guard.
3 shows that the door has been shut and locked down by a guard.
4 is only achieved by the General Manager (aka, warden) who has one of only three keys, refered to as the 'check' key. This is to lock down an area even from guard access, or comprimised keys. This level 4 lockdown throws the bolt out as far as it can go.
The level of lockdown can be seen from an indicator arrow which I didn't get a picture of. It uses the piece at the back of the lock, that has a connection to the bolt itself (Photo0124 shows it really well).
I don't know the brand or model of these locks, but I know they are designed to work with the PADDE MT112 eletric strikes.