Abstract: A control circuit bipolarly controls the stator of a 4-phase brushless DC motor in which the staor windings are connected in a ring circuit with only four semiconductor switches. Also, two control sequences are possible: a first control sequence consisting of four switching events per revolution and number of pole pairs, in which only two semiconductor switches are activated at a time, and a second control sequence consisting of eight switching events per revolution and number of pole pairs, in which alternately two and three semiconductor switches are activated simultaneously.

Abstract: An electrically commutated, collectorless direct-current motor is disclosed whose stator has a self-supporting drum winding and a cylindrical plastic body which is located concentrically with the drum winding in a winding head. The cylindrical plastic body has recesses which contain eyehooks. The ends of the drum winding are connected with the eyehooks, which are welded to a circuit board. The invention makes it possible to automate the connection of the winding ends to the circuit board.

Abstract: An electronically commutated, collectorless direct-current motor is disclosed whose stator has a drum winding and an external magnetic yoke surrounding same, and whose rotor consists of a shaft, a multipolar, permanent-magnet body, and an internal magnetic yoke. To reduce the moment of inertia, the internal magnetic yoke has kidney-shaped apertures. The direct-current motor exhibits a good dynamic behavior and is used in data processing equipment.

Abstract: An electronically commutated dc motor having a dome-shaped external rotor and a stator having a double-T-shaped design with the stator consisting of one yoke stack disposed asymmetrically in relation to the longitudinal stator axis and of two pole stacks of which each is provided with an extension on the same side in the longitudinal direction. In the circumferential direction the extensions are provided with lugs.

Abstract: An electronically commutated, collectorless direct current motor having a permanent magnet rotor comprised of a cup-shaped hollow cylinder in whose interior an internal magnetic yoke is arranged, an internal stator core and an external stator core. A stator drum winding comprises a plurality of phase windings wound on an insulating body with a portion of the stator winding being commingled with the phase windings in a plurality of slots of a slotted stator. The insulating body has a novel shape for arranging the stator winding thereon and for inserting the insulating body into a plurality of slots of the external stator core.

Abstract: An electronically commutated d.c. motor having a dome-shaped external rotor and a stator of a double-T-shaped configuration. Stator includes one yoke stack disposed asymmetrically in relation to the longitudinal stator axis. In addition, the stator includes two pole stacks each of which is provided on the same side with an extension in the circumferential direction. A printed circuit board is secured to a mounting flange of the d.c. motor.