by mac Sat Jan 03, 2015 10:08 am
Now I am going to say something heretical.
The lock on the right will not work as drawn. There are two problems. The first is the angle of the locking surface of lever 2 (counting from the nut). It needs to be less than 90 degrees to the line drawn from the pivot to the face. This face needs to be a sort of "ramp" so that the motion of lever 1 will cause lever 2 to rotate. This is a small thing and can be easily adjusted.
The second problem is more difficult to fix. The left end of lever 2 must lift the hook in the middle of lever 3. If we follow the arcs that Leonardo has conveniently provided, we see that it will jam under the hook before it can travel far enough to allow lever 1 to clear the working face of lever 2.
If I remember correctly, the text says something about lever 2 "breaking", so I assume the Leonardo realized that there was a problem, but had not gotten around to drawing a fix for it.
Mac