This is a series of drawings that I quickly made to show how the axis lock works. I didnt attempt to make my drawing resemble any knife in particular, with my skills it would have taken too long.
Starting with the knife in the open and locked state, this is a view from the side:
This view is of the knife in the open state with the front scale and liner removed. This view shows the Omega spring and the stop pin.
With the head of the Axis bar removed, we can see that the blade tang is actually wedged between the stop pin and the Axis bar.
To disengage the lock, move the Axis bar in the direction of the red arrow until it clears the blade tang.
This allows the axis bar to ride on the blade tang like a cam while the knife is closing.
Once the blade moves far enough into the closed position, the axis bar catches on the dip in the blade tang and begins to assist in closing the knife.
In the fully closed position, the axis bar and omega springs hold the blade closed
Hope this is useful,
-Duffin