i hope i can clear this up for everyone......
the bed frame is attached on either side to 2 metal arms that are spring loaded, allowing the bed to retract to a vertical position, usually recessed into a wall so it that it is flush with the wall when not in use. these metal arms are bolted to the frame with 3 bolts each. as i found out there are actually only 2 bolts per arm. thinking i had 1 bolt still firmly in place i removed the 2nd bolt - without safetying the arm - and viola. i was not hit by the spring, it did however cause the arm to retract almost instantly tearing through my forearm in the process. so there was no safety spring involved, i stupidly did not "safety" it or the arm first.
in retrospect i cannot understand how i could have concluded that the action was a good idea. it had something to do with saving some time, and i suppose it did since i was finished with the project in short order. the best part is that the guy i was helping, continued on and had the whole thing fall from the wall on top of him. yes he removed the bolts himself after witnessing first hand what removing bolts from a Murphy bed will do for you. luckily he escaped with superficial scrapes to one hand, and then, there amongst the clutter, he spotted the release button.