FIXING STRUCTURE AND FIXING METHOD OF YOKE AND CASE

摘要

A fixing structure and a fixing method of a yoke and a case prevents degradation of characteristics due to a leakage flux and an eddy current by not generating a crevice in a part where the rivet is coupled. A magnetic circuit(11) includes a magnet(12), a top plate(13) and a yoke(14) which forms the air gap so that the magnetic flux is vertically interlinked in the coil(2) correspondingly to the magnet and the top plate. A circle jaw(16) to which a curved surface(1a) formed by bending the bottom circumference of the case inwardly is pressurized, is prepared in the bottom of an outer circumference of a receiving surface of a yoke where a laminate of the magnet and the top plate is received. An annular protrusion(1b) is integrated in one direction of an inner circumference of the case.