Moving magnet type pickup cartridge

Claim 1

A pickup cartridge of the moving magnet type, comprising (a) a stationary yoke having at least three leg portions; (b) an armature; (c) means including a tiltably and oscillatably movable cantilever connected at one end with said armature for normally supporting said armature in a static position adjacent said yoke leg portions, said yoke leg portions being disposed in a plane normal to the axis of said cantilever when in the static position, a pair of said yoke leg portions comprising side leg portions arranged on left and right sides of said armature, respectively, the remaining yoke leg portions being arranged solely above said armature, whereby the area beneath said armature is open; (d) a phonograph needle connected with the other end of said cantilever for tilting and oscillating the same; (e) a pair of first coil means wound on said side leg portions, respectively, to provide channel signals in accordance with the inclination and oscillation of said armature based on oscillation applied to said phonograph needle; and (f) a pair of second coil means electrically connected with said first coil means, respectively, said second coil means being wound on those leg portions of said yoke arranged between said yoke side leg portions in such a manner as to cancel the voltages induced in one yoke side leg portion when the cantilever is tilted in one direction from said static position; (g) the end portions of said side leg portions adjacent said armature being disposed so that variation of magnetic flux, except that corresponding to inclination and oscillation of the armature based on oscillation applied to the phonograph needle, is cancelled magnetically.