Scotch Yoke mechanisms

[Piggiron]

Here's a couple links to short animated videos of Scotch Yokes with dwell. Here's the one with dwell at one end: https://www.youtube.com/watch?v=3SCbTB50csM
Here's another showing one with dwell at both ends: https://www.youtube.com/watch?v=I5ZwxzSrrO0

I had a short thread on Terry's temp site on possible methods for machining these.
After watching a few more videos, I'm hoping we have a math whiz or two here.
I've been unsuccessfully trying to find or figure some sort of equation that could be used to calculate the length of throw and the arc degree amount of dwell for these.
If my conclusions are correct, increasing the straight line segment lengths on either end should increase throw, but also decrease dwell.
I also considered that by flattening the arc, it should increase the throw while maintaining the dwell.
I know there has to be some sort of mathematical equation one could use to determine the variables for a desired throw and dwell, but I can't find one or figure one out.

[TerryWerm]

I tend to think that a single formula will probably not do the trick, but rather a couple of different formulas would be required. Since the results of one would affect the other, it is more likely that a series of formulas would be required. What they might be remains a mystery to me.

[Piggiron]

I tend to think that a single formula will probably not do the trick, but rather a couple of different formulas would be required. Since the results of one would affect the other, it is more likely that a series of formulas would be required. What they might be remains a mystery to me.

Could be for sure. The rotational diameter of the driver pin sets part of the equation as this would be a set value. The specific formula used would depend on what parameters are the desired outcome, those being stroke distance and angular dwell.

[Bill Gruby]

The diameter of the Driver Path is equal to the length of the Yoke Stroke (up and down ) Been quite a long time but that looks correct.

 "Billy G"

[Piggiron]

The diameter of the Driver Path is equal to the length of the Yoke Stroke (up and down ) Been quite a long time but that looks correct.

 "Billy G"

For a standard Scotch Yoke, you are correct Bill, but when the dwell arc is added in, it should shorten the stroke.
Here's another video link: https://www.youtube.com/watch?v=94ipooco_kg

This animation of a Scotch Yokes with dwell at one end seems to show that the stroke in both directions is equal, but that seem counter-intuitive to me.