PURPOSE: To remove a shock in the case of the failure of electric power and emergency stoppage during the high speed turning of a turntable using a motor having a spring brake type brake used mainly in the multistory parking garage for automobiles and of the turntable of a physical distribution carrier device, and further to make brake torque being little in brake noise variable.

CONSTITUTION: In the case of the stoppage of electricity and emergency stoppage during the high speed turning of a turntable, the pushing force of a brake spring 2 is weakened by an auxiliary spring 10 to slide a brake for removing a shock, or the auxiliary spring 10 is drawn back by a lever to strengthen the pushing force of the brake spring 2 for restoring the brake torque to a regular value. In addition, a motor brake having a structure for reducing brake noise can be obtained by attaching the auxiliary spring 10.