Abstract: In order to reduce, in a permanent magnet-excited electric motor with at least four poles, the cost for the machining and assembly of a magnet arrangement and to thereby lower the production costs, a magnet arrangement with a magnetic surface radially magnetized with an alternating pole sequence which is composed of three indvidual segments following each other in the circumferential direction, with a pole division extending beyond two adjacent individual segments.

Abstract: A low-cost, compact disk pack drive with an external rotor motor permanent magnet-excited by sintered ferrite magnets in the form of partial shells is to be provided. The external rotor motor is arranged inside the pack space of the disk pack and sintered ferrite excitation magnets are used, having a surface metallization which have been sealed.

Abstract: In order to be able to decrease the axial height, while simultaneously simplifying the manufacture, and also increasing the operational safety of printed circuit boards with electrical structural elements, such as Hall transducers affixed and electrically contacted to it further:(a) the printed circuit board contains, at least on one side, a supporting board (2) with recesses (21-23) in the area of each Hall transducer (4; 5; 6) and its connection legs (41-43; 51-53; 61-63) and on the other side a conductive foil (3) fastened to the surface of the supporting board (2), which covers the recesses (21-23) at least in the area of the free ends of the connection legs (41-43; 51-53; 61-63) and lands (44-46; 54-56; 64-66) for the connection legs of the Hall transducers; and(b) each Hall transducer and its connection legs is placed in a recess and the connection legs extend within the recess and include angle-bent ends connected to the lands.

Abstract: A permanent magnet-excited rotor motor is disclosed wherein, a circuit board (6) mounted on a radial motor attachment flange (22) is arranged. The front and rear sides of the circuit board (6) are equipped with conductor strips. On the front side, Hall transducers (15) influenced by rotor magnets (81) in a speed dependent manner are mounted. A flat cable brought in from the outside is divided into a first cable portion (12), passed through from the front with supply and signal voltage lines for the Hall transducers (15), and into a second cable portion (13) passed through from the back to the front with winding feed lines for the stator coil winding ends (14), which are likewise passed through from the back to the front of the circuit board (6) and thus can be soldered to the freely accessible front side.