Link calculations

[NickAdams]

I'm designing a pivoting clamp arm in proE using links and pivots,has anyone seen a way to calculate output force through a series of mechanical links and pivots, knowing the links sizes and angles plus the input cylinder force? I'm trying to achieve the best mechanical advantage, rather than disadvantage at the end of the stroke.

[JonathanHodgson]

Use the energy balance principle.

Specifically, compare the distance moved at the input and output of your linkage (for a small movement, since clamp linkages often have a ratio which varies with stroke).

Since energy in = energy out, [force in × distance in] = [force out × distance out], therefore the ratio of forces is the inverse of the ratio of distances.

If the distance moved at the output becomes zero, theoretically the force at the output is infinite and you've achieved a toggle clamp.