Man injured after elevator shot up out of control - GIF

[Frank S]

Passenger elevators come in basically 3 types friction drive, cable over hydraulic and direct hydraulic, 4 if you count magnetic linier drives, but the most common is a friction driven cable system using a huge counter weight depending on the size of the elevator car there can be a minimum of 4 cables to as many as 8 these are connected to an auto lock dead mans link above the car if they go slack for any reason the dead man's link locks the brakes on the car to prevent it from falling un controlled. in the pit under the car there is a bank of buffer springs or other devices to cushion the car if it happens to fall these may or may not be sufeincent to prevent injury or death if a car free falls from height.
the hoisting cables which raise and lower the car on friction drives pass over a huge grooved pulley one end connected to the mechanism on the car the other ends connected to the counter weight. With this type of lift system the only way a car can fall UP is for the car to be lightly loaded IE fewer passengers than excess weight of the counter weight and if the gears in the drive strip off or a shaft breaks. It looks like the car ascended somewhere around 30 floors so the acceleration by the time the car reached the top is anybody's guess. the counter weight could free fall at 32f per second per second but it would have also had the drag of the weight of the car plus the friction of the car riding up the guide rails,it still could have been going fast enough to bounce the man's head off the ceiling