Understanding the bearing block

[Ricardoco]

I've been reading around and now I'm going through the process of trying to understand what I've read. I'd be really grateful for a bit of help with the following questions.

I've been looking at the following axis design:

(taken from CNCRouterParts.com)

I'm trying to understand how the thrust bearings works in that setting? As far as I can tell, when assembled they would be in contact with the front/rear of the block not the radial bearing, so what would they achieve? The shaft collar is required here in order to keep the thrust bearings in place, would that be right?

Ok well this part i can answer for you. this would appear to be the cheapest way to avoid the latteral load from the axis being transmitted into the Motor bearing. the fact that the drawing above does not show a ballscrew is a little missleading. ive just done a quick drawing in paint that may make things a little clearer notice i say "may"

....

And yes the thrust bearings would "be in contact with the front/rear of the block not the radial bearing"

The radial bearing is not fixed to the drill rod but just a nice tight fit as a support for it. as you will know the shaft couplers are
fixed to the rods they couple together, the simplest way is with grub screws, in turn these are mated to the outside of the thrust bearings respectively leaving no play if at all possible, this diverts the latteral load through the trust bearing into the radial bearing block and on through the chassis it is connected to and hopefully not on to the motor!!!

there you go... Clear as mud

Please remember im no expert so my terminology may not be as it should be but only enough to be understood....Maybe lol