It occurred to me that a link that is used only to change the direction of link movement, like the one pictured below, is sort of an idler link. it’s like an idler pulley because it doesn’t do anything on it’s own. An idler pulley keeps tension in a belt, so it’s not quite the same, but the name seems at least a little appropriate.
Idler Link
This new link transfers motion from the upper crank down and across to the lowest level ball lifter.
Idler Link
Idler Link
Idler Link with Ball Connector
Idler Link with Ball Connector
Connecting Rod
Ball Lifter, Connecting Rod, and Idler Link
I had a little trouble making these parts. The connecting rod ends are made to fit around the standard 1/8” threaded spacers that I use everywhere but that made the ends too big to fit next to the larger tube that holds the bronze bearing. I had to file down the outside of that tube between the two side pieces so that it would not bind. The new idler link had much less clearance than the previous ball lifter part. Both with need a little more work if the connecting rod itself hits the bearing tube when the links are moved all the way in one direction or the other. We’ll see.