摘要 |
<p>An electrically-operable actuator 10 which includes a reversible direct current electric motor 16, a reduction gear train and a reciprocable member 96 adapted at one end to be coupled, for example with a locking lever of a motor vehicle door latch has, in the reversible direct current electric motor 16, a permanent magnet stator 18 in the form of a cylindrical ring, the internal diameter of which is at least twice the actual length thereof; a coil-wound armature 24 in the form of a salient pole rotor having a diameter of at least twice the actual thickness thereof; and a flat disc-shaped segmented commutator secured to said rotor concentric with, and adjacent, a pinion output gear 40 on said rotor. In a preferred embodiment of the present invention, the actuator includes a rotary load-sensitive releasable coupling 64 within said reduction gear train which disengages said reciprocable member 96 completely from said reversible electric motor 16 at the end of each predetermined motorized movement of said reciprocable member 96, so that, when said reciprocable member 96 is coupled to said locking lever of a motor vehicle latch and the actuator 10 is inoperative, said locking lever can be operated manually without undue difficulty.</p> |