This is appalling to my minifigs... ^^"
The carriage falls at top speed due completely to gravity. Basically speaking, bricks will be loosed a little bit after 3-4 falls but the machine can still function properly. No bricks will be detached or torn apart, except that a little hand of one of the minifigs fall out after perhaps 40 falls (ref: the following picture) ^^"
The following pictures show how it functions:
Want to see it in motion?