エタノール中DCモータにおける整流過程のアーク発生現象：ブラシ・整流子の接触状態に基づく考察

抄録

For an experimental DC motor equipment immersed in ethanol and gasoline, commutator currents were measured at various rotational speeds to find out an arc duration time during commutation process and a residual current. The result revealed that the arc duration time for the ethanol was 3-6 µsec and this duration time was longer than that for the gasoline. The residual current in the ethanol also proved to be 2-3A and to be about twice higher than that in the gasoline. Subsequently these results were discussed on the basis of contact resistance just before brush-commutator separation. As a result, the contact resistance was found to be 0.6 times lower in the ethanol than in the gasoline. A novel approach was lastly made to the contact state of the brush on the commutator in view of mechanical properties: coefficient of friction, lubrication, contact load. This approach achieved successful explanation of the phenomena above.