I am trying to open a brushless DC fan of computer Belkin cooling pad. I have accessed the fan from the cooling pad. I don't see any screws to deattach the fan from the motor. Please see the images below,
if you can see at the bottom of the motor , you'll see the rotor shaft. around that shaft there's a ring maybe of plastic , rubber or a metal . By removing that ring you can remove the whole fan from the stator part of motor. This is because of a sleeve ring cut at rotor's shaft towards inside to lock it with the stator .