An emergency braking system for a machine tool for the abrupt braking of a rotating shaft, including at least one brake drum and at least one brake shoe which are brought into engagement with each other in order to brake the shaft, the brake drum engaging with the brake shoe under the influence of a centrifugal force resulting from the rotation of a shaft. The present system is configured in such a way that at least one resetting device is provided which makes it possible to reset the brake shoes in the direction of their original position after braking has taken place.