| 摘要 |
<p>1323342 Electric motors; inverting AGENCE NATIONALE POUR LA VALORISATION DE LA RECHERCHE 9 June 1970 [10 June 1969] 27726/70 Headings H2A and H2F In a brushless D.C. motor, the iron rotor 25 is bell-shaped and carries a series of permanent magnets A 1 ... A 8 on its inner surface which co-operate with main winding B 1 B<SP>1</SP> 1 ... B 3 B<SP>1</SP> 3 mounted circumferentially on the stator core Fe. A flat magnet A 9 on the base of the bell, Figs. 4 and 5 (not shown), provides 4 pole pairs which co-operate with windings (b 1 , b<SP>1</SP> 1 ... b 3 , b<SP>1</SP> 3 ) on the end face of the stator core to control electronic switching devices supplying current to the main windings. The ring Fe may be of non-ferromagnetic plastics material. The motor may be used as a pilot motor in a D.C.-A.C. converter employing a transistor bridge T 1 -T<SP>1</SP> 3 , Fig. 6. The motor m drives a position sensor CT which may be an inductive pick-up of the type depicted in Figs. 4 and 5. The output frequency may be varied by altering the speed of the pilot motor. In a constant frequency converter, Fig. 7 (not shown), the transistors are triggered by the output signal of a synchro driven by the pilot motor whose speed is stabilized by a tuning fork oscillator. The output phase sequence may be reversed by reversing the pilot motor or by altering the output of the sensor CT.</p> |
