Abstract: The electric motor is of the type in which the speed of rotation as a function of the resisting torque is different in one direction of rotation than in the other, and comprises a pair of brushes (B1, B2) placed between field poles (P1, P2) and cooperative with an armature structure consisting of a commutator (14) rigid with an armature support (12) through which the shaft of the motor extends and in which are formed slots in which are wound wires connecting a series of strips (1,2 . . . ) of which the commutator (14) is formed, wherein each plane (L) containing the geometric axis (XX) of the motor and passing through the middle of a strip (1,2 . . . 8) of the commutator (14) halfway between two consecutive slots (15) of the commutator is offset by a given angle .beta. relative to the corresponding plane (K) passing through two diametrically opposed slots (B,F) of the armature support (12) in the direction of rotation (R) of the motor employed for the rising of the driven element.

Abstract: The commutator comprises three conductive sectors 2 which are maintained against a cylindrical insulating core 4 by an insulating ring 3. Cut out from the rear end portion of each sector is a terminal 11 which defines two tabs 12 projecting axially at the rear end of the sector. Each pair of tabs straddles a parallelepipedic projection 5 of the core 4. The three sectors are maintained radially and axially in position by the ring 3 which comprises an annular portion 15 from which extend three claws 16 in the longitudinal direction, the claws being clipped behind a flange 6 which projects from the core. In this way, it is possible to mould the core and the ring 3 from a thermosetting material and to improve the maintenance of the sectors 2.

Abstract: Mounted on the slidable element is a transverse spindle which is guided in rectilinear translation. A driving gear pinion meshed with a fixed longitudinal rack is fixed on the spindle. The device comprises a toothed member which is pivotally mounted on the front end of the rack and has a set of teeth including a curved front portion and a rectilinear rear portion. A device is provided for constraining the pinion to remain meshed with the curved portion at the end of the closing travel.