FIELD: electric motors for drives of additional equipment of such vehicles as cars and tractors. SUBSTANCE: device which is excited by ferrite magnets has armature with winding and collector and cylindrical magnetic-conducting housing, which trailing edges of segment-shaped poles are extended to commutation area and crosses geometric neutral line of motor. Extended areas of poles have lesser magnet length with respect to main segment-shaped areas, which are located in working pole area of electric motor. In addition external surface of pole pairs which are extended to commutation area is shaped as extension of circumference arc which shapes external surface of main segment-shaped areas. Optimal shape of inner surface of trailing edges of segment-shaped poles which are extended to commutation area is produced by curve or polygonal line so that minimal length of magnet of extended areas is located at border of commutation area with trailing edge of main segment-shaped area of pole; while maximal length of magnet of extended areas is located at geometric neutral axis of electric motor. EFFECT: increased reliability, increased service life of brush-collector unit due to better switching in nominal mode by means of magnetic induction which is caused by armature current in neutral area by magnetic field of trailing edges of poles which are extended to commutation area. 3 cl, 2 dwg
