We also removed our broody from the flock to adopt some day old chicks.  The brooder is in the barn and hen/chicks can access a fenced off area in the main run.  The adoption occurred 3rd week of Feb - so really cold and windy weather and we kept them in the brooder for around 1.5-2 weeks before we could let them into the run based on weather.  This was momma hens second batch of adopted chicks.  
When we let them into the  run, we used moveable fencing that we added mesh fencing to so that the chicks could not get away from momma's protection.  While the top was open, it is about 3' high, so no adults flew over in either direction.   Funny enough, a couple of chicks learned to fly up to the top of that fence and perch.  It would have been easy for them to then fly into the main run, but none of them ever did, they would turn around and fly back to momma - however, I wouldn't rely on all chicks to be wise enough to remain on the momma side.   Soon enough, the weather improved and the chicks got more feathers, and we enlarged their area and allowed the flock to get up and around their area for more see-no touch integration.   Then about a week ago, we opened up the fence so they could have access to whole run, and momma hen was still protective and kept the rooster and a few of the opinionated hens away from her chicks.   Today (they are 6.5 weeks old), they are blocked from entering their brooder, although we will allow them to sleep there for another couple of nights.    Overall, our integration with this batch has gone slower than I anticipated due to the weather conditions.  My expectation was to have them start to sleep in the coop by 6 weeks old, however, they will be more like 7 weeks old or so when that happens.  The integration in the coop at bedtime is a whole other event - they are quite serious about roost space and position, so I want the older chickens very familiar with the chicks during the day.  
Our other batch of momma hen raised chicks happened in the fall.  Once we completed daytime integration, and put them in the coop, they figured out their places within a couple of weeks with space on the lowest roost and squabbles were minimal.   However, those chicks remained as a group and it wasn't until they got closer to point of lay that they really and fully integrated with the flock, which is fairly common it seems.
Here are the latest batch of chicks on their first day in the fenced off run area.  At this point, the rest of the flock could get close to this fence, but not right up to it.  They were all fascinated by the chicks!