Abstract: Field magnets are attached to an inner periphery of a stator core, which defines a rotor through hole. The stator core has a plurality of recesses open to the rotor through hole. Each recess faces magnet end portions of the field magnets. The recess surface of the recess is away from the surface AC of the magnet end portion and set back toward an outer periphery of the stator core from a rear surface AD of the magnet end portion.

Abstract: Field magnets are attached to an inner periphery of a stator core, which defines a rotor through hole. The stator core has a plurality of recesses open to the rotor through hole. Each recess faces magnet end portions of the field magnets. The recess surface of the recess is away from the surface AC of the magnet end portion and set back toward an outer periphery of the stator core from a rear surface AD of the magnet end portion.

Abstract: A drive apparatus includes a commutator motor having a hollow rotation shaft with an internally threaded section provided therein and a flexible power transmission cable inserted through the hollow rotation shaft such that a spiral thread-like rib of the cable engages with the internally threaded section of the hollow rotation shaft, whereby a propulsive force is transmitted to the cable to allow a window glass to be moved in a reciprocating motion. A guide roller with an intermediate section of the cable wrapped therearound is rotatably supported on a guide base to allow the passage of the cable. A curved guide section is provided relative to the guide roller to define a curved cable passage channel in a manner to cover a wrapped cable portion. The guide roller is rotated by the commutator motor through the cable, while the intermediate portion of the cable is pressed onto the guide roller.