Tachometer generator

Abstract

Abstract PURPOSE:To prevent the effect by the temperature drift of permanent magnet of a tachometer generator by a method wherein a negative temperature coefficient resistance means is connected in series to the armature winding. CONSTITUTION:A negative temperature coefficient resistance means 8 is attached closely to an armature core 2 of a tachometer generater. By this way, although a voltage Eo induced in the armature winding is made to vary by the effect of temperature variation of permanent magnet 4, because the variation of voltage is compensated by the variation of resistance Rth of the negative temperature coefficient resistance means 8, the terminal voltage Et is not affected by the temperature drift of permanent magnet 4. Therefore the low-cost ferrite group magnet can be used for the permanent magnet 4.

Inventors

• 👤 Sumio Kobayashi

Bibliographic Details