ROTATION DETECTOR IN COMPRESSOR

摘要

PURPOSE:To detect the rotation of a rotor even if a magnetic detector is disposed on the outer surface of a casing by composing the detector with an amorphous alloy wire as a core material by winding a coil on the outer periphery. CONSTITUTION:A magnetic detector 11 is so fixed on the outer surface of a sealed casing 2 of a compressor which contains a rotor 1 having a magnet 8 on the outer periphery as to correspond to the rotating locus of the magnet 8. The detector 11 is provided by winding a plurality of turns a coil 17 with a plurality of amorphous alloy wires bundled as a core 15, disposing in parallel the core 15 to extend along the circumferential direction (rotating direction) of the rotor 1 in an adjacent state, and sequentially connecting in series the coils 17. When the compressor is operated, a magnetic field abruptly increases or decreases as the magnet 8 on the rotor 8 passes the lower part of the detector 11. At this time, the detector 11 abruptly generates the inversion of the magnetic flux, thereby generating an alternating pulselike electromotive force.