Claims
- 1. 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.
- 2. The developing magnet roll according to claim 1, wherein said hollow, cylindrical permanent magnet member is made of an isotropic ferrite magnet material, and said thermally demagnetized portion is formed on both circumferential sides of said developing magnetic pole.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4-267759 |
Oct 1992 |
JPX |
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Parent Case Info
This is a continuation of application Ser. No. 08/130,195, filed Oct. 1, 1993, now U.S. Pat. No. 5,539,368.
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Continuations (1)
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Number |
Date |
Country |
Parent |
130195 |
Oct 1993 |
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