I do the opposite with mine. I separate while they are sitting and til the chicks are a couple days old and wanting to run around, then I put them all together. This way when mama quits mothering them (in 4 or 5 weeks, usually) the flock is already used to the chicks. I've also let the broody sit on the eggs while in with the rest of the flock. I've had some chicks hatch this way, but sometimes the mama returns to the wrong nest after getting up for her once a day outing, sometimes the eggs get moved around, stolen or cracked, etc. So far I haven't had a problem with young chicks being in with the flock, though of course it can happen. The mama keeps others away from the chicks -- and sometimes the roo helps watch out for the chicks.
In your situation, I probably wouldn't separate now because, as the other poster said, moving a broody can cause her to stop setting. If you do move them and one stops, though, at least you have another who could certainly take the other eggs, at least if you set them all about the same time. If you decide to move them while setting, I'd do it early in the night and I'd move as much of the nest (at least the litter) as possible along with her. I did move a broody successfully once when she was setting in a plastic bin, so I could just pick up her and the bin at once.