PURPOSE: To surely detect the running direction of an escalator, facilitate restart, and improve reliability, by connecting a rotary fluid pump to the low speed rotating shaft of a driving device, and providing limit switches on both ends of a double acting type actuator driven with the shaft.

CONSTITUTION: A rotary type fluid pump 13 is coupled with the low speed rotating shaft of a driving device, a double acting type actuator fitted with a piston 20 having orifices 21 and its return springs 23, and a reverse rotation detecting switch 1 constituted out of limit switches 26 acting with dogs 25 fitted on both ends of the actuator, are provided on this. By this constitution, at stop of the rotating shaft, the limit switches 26 for normal and reverse rotation are neutral by action of the return springs 23. At rotation of the output shaft in either direction, one of the limit switches in ON and the other is OFF, and it is changed over at reversing. Consequently, three conditions, normal rotation, reverse rotation, and stop can be expressed.