Ok, this is going to be in laymens terms, bear with me!
So when the trigger is pulled, it disengages the sear from the 2 notches (full cock and half cock, respectively) on the unseen part of the hammer, allowing the hammer to fall and a round is fired. After the round leaves, the recoil drives the slide back, and the slide moves, meaning that the little half-moon shaped recess the upper part of the disconnector sat in moves, driving the disconnector downward, which conveniently places itself in the way of the trigger so, had it not been there, the trigger would continue to put pressure on the sear, driving it back indefinitely as the trigger was held and thereby causing an automatic stream of fire. So, with the trigger no longer putting pressure on the sear (because it is blocked by the disconnector), the full cock notch in the hammer is caught by the sear during the rearward motion of the hammer caused by the rearward movement of the slide. So, after the slide is back again in place, with the hammer at full cock, the trigger is released, releasing the disconnector into its little half-moon notch under the slide, where it remains until the next pull of the trigger.
Have I got it?
The disconnector actually connects the sear to the trigger via a little paddle shaped end when it's in its little notch. When fired and the slide recoils, the disconnector is pushed down and the paddle at its bottom end no longer bridges the gap between trigger and sear. The sear is free to catch the hammer again and the trigger must be released to allow the disconnector to rise and bridge the gap between the sear and trigger for the next shot.
Thanks for the correction!
That's probably why its called a DISconnector... oops.
So the rest is right?
BigG nailed it. The disconnector is actually a connector AND a disconnector.
The half-moon notch is the disconnector's timing slot. When the slide moves, the disconnector is cammed down by the flat area on the center rail, driving the disconnector down away fron the sear and trigger, and allows the left leg of the sear spring then rotates the sear back toward engagement with the hammer hooks.
When the slide moves into battery, the timing slot lines up with the top of the disconnector and it's free to move upward to bridge the gap between trigger and sear. Now it's a connector again. Stay tuned and I'll post a link that lets you see the insides of the gun in a cut away during the cycle. It will be on this reply after an edit.
Here it is. The pictures will take a few minutes to load.
http://www.m1911.org/locking.htm
What does it mean when you say the slide moves 'into battery'?
Battery - means it closes for the next shot.
The part really should be called the connector and we should say that the connector is disengaged and the connection in broken.
A true disconnector acts to break the trigger-sear connection; the M1911 disconnector IS the trigger-sear connection.
And so...
The disconnector is actually a connector..until the slide moves, and then it's a disconnector. If the disconnected connector doesn't reset, it's not a connector, and there fore is a disconnected connector until it gets fixed and reconnects with the trigger and sear, and becomes a connector again.
Are we confused yet?