Torque-limiting stop device

In a reversible electric motor comprising a casing mounted rotatably on a fixed support coaxially with a driving shaft of the motor and rotatable in either direction from an angular rest position against the action of biasing means, a torque-limiting stop device actuable in response to rotation of the casing from said rest position when an opposing torque on the motor shaft exceeds a predetermined value, comprising cooperating complementary profiles in hollow and in relief one of which is angularly fixed relative to the motor casing and the other angularly fixed relative to the fixed support and one of which is on a mobile element movable by coaction of the cooperating profiles against the action of said biasing means in a direction substantially perpendicular to the direction of relative movement of said profiles produced by said rotation of the motor casing from its rest position, said hollow profile being extended on either side by a bearing surface substantially perpendicular to said direction of movement of said mobile element and a stop limiting the relative angular displacement of the motor casing from said rest position, each said profile in relief being able to rest on a corresponding bearing surface of a hollow profile to cancel the action of said biasing means tending to return said casing to its rest position, first and second means for stopping the motor driving said shaft in respective opposite directions, and at least one actuator fixed angularly with said casing for selectively actuating one of said first and second stop means to interrupt drive of said shaft in a respective direction when each profile in relief is on a respective one of said bearing surfaces and prevent restarting of the motor shaft in the same direction of rotation as before.