Magnet roll and method of producing same
AssigneeHitachi Metals, Ltd.
InventorKeitaro Yamashita
Life of this patent
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Abstract
The magnet roll of the present invention includes a shaft and a permanent magnet member fixed to the shaft, the permanent magnet member being composed of a hollow, cylindrical magnet body, and a magnetic pole piece fixed to a recess of the hollow, cylindrical magnet body, the hollow, cylindrical magnet body having a plurality of axially extending magnetic poles arranged circumferentially on the surface, the magnetic pole piece being provided with two magnetic poles having the same polarity for constituting a developing magnetic pole, and a thermally demagnetized portion being formed substantially at a center of the developing magnetic pole such that the permanent magnet member generates a magnetic flux density distribution having two peaks of the same polarity at a position of the developing magnetic pole.
Claims2
A developing magnet roll comprising a shaft and a hollow, cylindrical permanent magnet member fixed to said shaft, said permanent magnet member having:
- magnetic brush forming means comprising a plurality of magnetic poles extending axially and disposed at a certain interval circumferentially on a surface of said permanent magnet member;
- and
- a thermally demagnetized portion being formed on at least one circumferential side of a developing magnetic pole such that said permanent magnet member generates a steep magnetic flux density distribution at a position of said developing magnetic pole.
Dependencies are inferred from the claim text.