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US4303844A Expired / Lapsed US ⏱️ 0.0 years remaining

Small D.C. motor

Assignee: Alps Alpine Co Ltd
•
Filing: 1979-08-27
•
Granted: 1981-12-01
•
Expires: 1999-08-27
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Abstract

Abstract A D.C. motor is disclosed having a magnetic plate disposed on the upper surface of the rotor for normally urging a rotor of the motor downwards. The spacing between the magnetic plate and a cover plate of the motor is made larger than the spacing of the rotor from the cover plate to ensure that the magnetic plate will not be unduly attracted to the cover plate.

Inventors

  • 👤 Tadashi Suzuki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 17:09
CPC Classifications
H; H02; H02K; H02K23/00; H02K23/54; H02K7/00; H02K7/08; H02K7/09

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 112 words
A motor including a substantially cylindrical housing made from a magnetic material; a rotor member mounted within said housing and having a plurality of coils formed therein; a rotary shaft held to a center portion of said rotor member; a permanent magnet fixed in said housing and spaced from one surface of said rotor member; a magnetic element held concentrically to the other surface of said rotor member; a thrust bearing secured adjacent said permanent magnet to said housing and adapted to receive an end portion of said rotory shaft; and the wall portion of said housing adjacent said magnetic element having a raised portion formed therein adjacent to said magnetic element.
Claim 2
Dependent Claim 112 words
A motor including a substantially cylindrical housing made from a magnetic material; a rotor member mounted within said housing and having a plurality of coils formed therein; a rotary shaft held to a center portion of said rotor member; a permanent magnet fixed in said housing and spaced from one surface of said rotor member; a magnetic element held concentrically to the other surface of said rotor member; a thrust bearing secured adjacent said permanent magnet to said housing and adapted to receive an end portion of said rotory shaft; and the wall portion of said housing adjacent said magnetic element having a raised portion formed therein adjacent to said magnetic element.
Claim 3
Dependent Claim 24 words
The miniature motor according to claim 1, said thrust bearing being formed of a synthetic resin and having a brush holder formed integrally therewith.
Claim 4
Dependent Claim 33 words
A motor according to claim 1, said rotor member being made of a synthetic resin and its upper surface being formed integrally with a plurality of first protrusions for fixing said magnetic element.
Claim 5
Dependent Claim 26 words
A motor according to claim 3, said magnetic element being held by said first protrusions and fixed to said rotor member by thermally deforming said protrusions.
Claim 6
Dependent Claim 28 words
A motor according to claim 1, further including a varistor fixed to said one surface of said rotor member, said varistor being fixed concentrically with said rotor member.
Claim 7
Dependent Claim 32 words
A motor according to claim 5, said rotor member being made of a synthetic resin, and its lower surface being formed integrally with a plurality of second protrusions for fixing said varistor.
Claim 8
Dependent Claim 26 words
A motor according to claim 6, said varistor being held by said second protrusions and being fixed to said rotor member by thermally deforming said protrusions.
Claim 9
Dependent Claim 13 words
A motor according to claim 1, said magnetic element being generally ring shaped.

References Cited (Backward Citations)

US3226586A Cited
US3239705A Cited
US3167675A Cited
US3204137A Cited
US3525007A Cited
US3737697A Cited
US4079277A Cited
US4188556A Cited
US4208784A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-30 1985-06-01 1985-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-30 1989-06-01 1989-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-30 1993-06-01 1993-12-01 $7700.00 Window Closed / Lapsed

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