抄録
Three types of rotors were made and installed into a commercial brush DC motor. Motor performances were measured to know the effects of magnetic properties of rotor materials. The materials used as a rotor were two types of iron powder cores with flux densities of 1.60T or 1.70T at 10 kA/m and a lamination steel (SPCC) core with a flux density of 1.82T, respectively. The efficiencies of the iron powder motors were 68% or 70% and that of the lamination steel motor was 64%, therefore the motor efficiency was improved by about 6%. Two types of iron powder motors and the lamination steel motor gave almost the same output torques at the speeds of 4,250 to 5,350 rpm, although the flux densities of the iron powder cores were smaller than that of the lamination steel core. These results indicated that the iron powder cores enhanced the performances of the brush DC motor.