Pickup cartridge with magnet armature having opposite axial sides of like polarity and central portion of opposite polarity

Claim 2

A pickup cartridge comprising an armature comprising a permanent magnet of a flat plate magnetized in the axial direction in the same polarity on both outer sides and in the opposite polarity at the central portion boundary plane, a stylus arm coupled to said armature, a stylus mounted on the end of said stylus arm, a yoke of the substantially inverted channel shape and a coil wound on said yoke, said armature being supported approximately at its center of gravity, said stylus arm being movable in all angular directions, said yoke having a pair of pole pieces disposed in the proximity of said armature.

Claim 3

A pickup cartridge according to claim 1, wherein said armature in the form of a flat plate consists of an integral single magnetic material.

Claim 4

A pickup cartridge according to claim 1, wherein said armature in the form of a flat plate consists of two flat magnet plates which are bonded with each other and magnetized in the axial direction in such a manner that portions of one polarity of the respective magnet plates are brought into contact with each other.

Claim 5

A pickup cartridge according to claim 1, comprising a pair of substantially inverted-channel shaped yokes disposed in the proximity of the outer periphery of said armature, said yokes being wound with coils connected in series with each other.

Claim 6

A pickup cartridge according to claim 1, comprising a pair of substantially inverted channel-shaped yokes disposed at right angles to each other in the proximity of the outer periphery of said armature.

Claim 7

A pickup cartridge according to claim 1 in which said armature is provided with a section in the shape of a semicircle,

Claim 8

A pickup cartridge according to claim 1, in which said armature is only partially magnetized.

Claim 9

A stereophonic pickup cartridge comprising an armature of a flat disc-shaped magnet magnetized in its axial direction and having magnetic poles of the same polarity set up on both outer sides and magnetic poles of the opposite polarity formed in its central portion at the boundary plane, a stylus arm coupled to said armature, a stylus mounted on the end of said stylus arm, a support member with a notch portion for supporting said armature approximately at its center of gravity, a damper of elastic material interposed between said armature and said support member for allowing said stylus arm and said armature to vibrate around said center of gravity, a pair of substantially inverted channel-shaped yokes disposed at right angles to each other for effecting stereophonic reproduction from a stereophonic grooved sound record and coils wound on said yokes, said yokes being provided with pole pieces at their ends disposed in the proximity of the outer periphery of said armature.

Claim 10

A stereophonic pickup cartridge comprising an armature of a flat disc-shaped magnet magnetized in its axial direction and having magnetic poles of the same polarity set up on both outer sides and magnetic poles of the opposite polarity formed in its central portion at the boundary plane, a stylus arm coupled to said armature, a stylus mounted on the end of said stylus arm, a support member with a notch portion for supporting said armature approximately at its center of gravity, a damper of elastic material interposed between said armature and said support member for allowing said stylus arm and said armature to vibrate around said center of gravity, a pair of substantially inverted channel-shaped yokes disposed at right angles to each other for effecting stereophonic reproduction from a stereophonic grooved sound record and coils wound on said yokes, said yokes being provided with pole pieces at their ends disposed in the proximity of the outer periphery of said armature.

Claim 11

A stereo pickup cartridge according to claim 8, comprising four inverted channel-shaped yokes placed at right angles to each other in the proximity of the outer periphery of said armature, wherein coils wound on each of pairs of said yokes arranged at 180* to each other are connected in series.

Claim 12

A pickup cartridge according to claim 8, in which said armature is provided with a section in the shape of a semicircle.

Claim 13

A pickuP cartridge according to claim 8, in which said armature is provided with a section in the shape of a V.

Claim 14

A pickup cartridge according to claim 8, in which said armature is provided with a section in the shape of a +.

Claim 15

A pickup cartridge according to claim 8, wherein said disc-shaped magnet comprises two disc-shaped axially magnetized plates, said plates being bonded to each other at surfaces of like polarity.