Speed reducer with emergency braking function

The utility model belongs to the technical field of speed reducers, and particularly relates to a speed reducer with an emergency braking function, which comprises a machine body assembly and a braking assembly, the machine body assembly comprises a machine box, a mounting frame mounted on the side of the machine box, a motor arranged on the other side of the mounting frame, a driving shaft fixed to the driving end of the motor, a gear sleeve mounted on the driving shaft and a first gear connected to the gear sleeve in a meshed mode. The first transmission shaft is fixed to the middle of the first gear and assembled on the mounting frame, the second transmission shaft is in transmission connection with the first transmission shaft and assembled on the mounting frame, and the output shaft is in transmission connection with the second transmission shaft and extends out of the side face of the mounting frame. Through the working brake and the emergency brake, when the motor is powered on, the emergency brake is