Patent ID: 8783277

Claim:
A position-detecting method for an actuator in which a rotational driving force, generated in an electric motor, is transmitted to an object to be driven, through the intermediary of a reduction mechanism, characterized by: feeding an electric power from a battery to minimum necessary circuits of a control section during a power failure; further feeding an electric power from said battery to a resolver for detecting a rotating state of an output shaft of said electric motor during the power failure, when said control section detects an ON-state of an interlock switch which represents that an input shaft of said reduction mechanism is linked to a manual inputting means rotationally driven by a person's driving operation, so as to be rotated; and obtaining a displacement of the object to be driven based on a signal which is output from said resolver, and which is related to the rotating state of the output shaft of said electric motor resulting from the person's driving operation.