Continuous relative tracking around a pivot

[Pandamonium]

Not quite sure the title is right, but it's the best I've been able to piece together. Link below is to a thread on another forum where a dude used some pretty expensive tooling to do what I'm trying to do for cheaper.

Table saw mechanism

Restoring an old table saw, Delta 34-441 (same as 34-444 or 34-445). Anyway, the basic underpinnings of my saw and the thread above are the same.

The sawblade is mounted on an arbor shaft that rotates around a pivot point. I want to retrofit a riving knife for kickback protection. The riving knife needs to be contoured to the sawblade and track with it. My problem is that the sawblade is "raised" and "lowered" about the pivot point, so tracking is nonlinear.

I really like the guy's modification, but my only hangup is that I wonder what happens if the idler bearing wears prematurely. If the saw is spinning and the idler bearing catches, I would think that the table saw torque would rip the assembly off the mounts and possibly bring metal into contact with the sawblade. That seems kind of dangerous. I'm thinking there should be another way to mechanically fix a point relative to another nonlinear point, but I don't know how. So I figured someone here might. Ideas?

Also, it's been a while, so if anyone has suggestions for the thread title, I'm all ears.

 

[Pandamonium]

Found some pictures that illustrate the problem courtesy of others...

original post

(image from fine woodworking/google cache)

There must be some way to attach a riving knife that tracks with the rotation of the sawblade. I'm still thinking about it myself, but figure there must be a way. (that doesn't require adding a bearing to the sawblade shaft.)