I can't figure out how this one works.

[bigfatross]

Hi Gang,
I came across these photos surfing the web. I can't figure out how this one works, when the blade is closed
I assume the spring stretches.
What I'm confused on is when the blade is folded closed, it looks like the spring would bind up, another words not
enough room for the spring to move with the arc of the closing of the blade. I believe this is called a "torsion" opening knife?
Any ideas, explanations, thoughts, or diagrams?

In your opinion, what is your favorite or most durable spring opining configuration?
I would have to say a leaf spring, judging from some of the antique knifes that still have the original spring.
Thanks in advance!

[ILikeStilettos]

First note that the liners are cast, not cut from a flat sheet ... I guess that the pommel and bolsters are cast at the same time. The spring is pinned to the back liner and hooked to the tang of the blade. The floating back spring that makes for the lockback is pinned all the way through. I can't tell from the photos, but probably a more or less standard rocker on the front liner. When you close the blade, you tension the spring.

[JimBrown257]

The torsion spring is different than this. If you have one of those switch-combs, look at the kickspring in it; that is a torsion spring.

This Spanish knife has a compression spring. I've only ever seen it on this knife and the black scales Matador. It works really well and fires super hard but it is probably more complicated than it needs to be. If the spring were to break, you would have a tough time getting it replaced.

The thing that you see the top that the spring is hooked to is actually a third piece that is hooked to the bottom of the blade. Having that middle piece allows the whole operation to be fit in a smaller area than it would if the spring was hooked directly to the blade, When the blade is closed, the spring is pulled up well into the bolster area. So when the button is pushed, the spring pulls down which pulls the bottom of the blade down and the top goes up.

The spring is so strong and the slight diagonal pull from the back of the bolster to the bottom of the blade causes the handles of these knives to becomed slightly curved over time.

And the button set-up is a lot like the modern two-piece. The lock is pushed back by a small spring bar like in the traditional manual lockback.

[bigfatross]

Very Interesting!
Thanks Guys!