Puzzle Lock?

[Locust]

Does anyone have any good video, pictures, or diagrams of how a Bram Frank Puzzle Lock works? From pictures I originally thought it operated like a back lock but in an old Spydercoforums thread Bram Frank mentioned that the principle is similar to a liner lock.

 

[jbgecko13]

here is the patent for it
http://www.google.com/patents?id=fNzHAAAAEBAJ&zoom=4&dq=puzzle%20lock%20knife&pg=PA10#v=onepage&q=puzzle%20lock%20knife&f=false

 

[Sword and Shield]

Reading the patent, it's a cross between the two. Locking and unlocking is similar to a liner lock. However, the mating surfaces, being more than a simple bar, makes it closer to a backlock in shape.

 

[Alanp]

Looks like a frame lock and a compression lock hugged a little to long and this was the outcome several months later.

 

[jimnolimit]

looks like a compression lock to me.

 

[effer]

Yeap, looks like compression lock. Can't see the difference between that lock and lock on Spyderco Paramilitary

 

[jimnolimit]

Yeap, looks like compression lock. Can't see the difference between that lock and lock on Spyderco Paramilitary

yeah, the only difference i noticed is the shape of the notch on the back of the blade. the para has a rounded notch and the puzzle lock has a square notch.

 

[TurboScooter]

Yeap, looks like compression lock. Can't see the difference between that lock and lock on Spyderco Paramilitary

As for the lock.. Its not a compression lock..its not a variation on a compression lock..
A locking liner has a tang arm that rotates out and its not a compression lock..and yes a liner could operate from the top side as well as it does from the bottom as it normally does..
the fact that a compression lock and a puzzle lock have back releasing tang arms doesn't make them the same or related by function.
no anvil pin, no compressing action, then no compression lock..
a puzzle lock does NOT compress...
a puzzle lock has no anvil pin or pinning action..
as for overall quality its as good or better..
personally I think its better..I personally choose the materials used.

I think the difference is the compression lock wedges the liner between the blade tang and the stop pin, but the puzzle lock fits the liner into a matching slot in the tang itself. In the puzzle lock patent there's a section that describes the weakness of the compression lock, which seems to revolve around the deformation or loss of the stop pin.