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US3969642A Expired / Lapsed US ⏱️ 0.0 years remaining

Step motor for electronic timepiece

Assignee: Suwa Seikosha KK
•
Filing: 1974-07-17
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Granted: 1976-07-13
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Expires: 1994-07-17
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Abstract

Abstract A step motor particularly suited for use in electronic timepieces wherein the induced current generated by the stepping of the rotor is utilized to minimize the power consumption thereof. The step motor includes a permanent magnet rotor adapted to be stepped through a specific angle, at least two stator poles surrounding same, and an electromagnetic core coupled to the stator poles for providing at least first and second magnetic orientation to said stator poles in order to step said rotor through the specific angle. Coupled to the electromagnetic core is a circuit for applying driving pulses to the stator pole to effect said orientations thereof, and a second circuit coupled to said first mentioned circuit for terminating each drive pulse applied to said electromagnetic core at a time coincident with completion of the stepping of the rotor through the specific angle.

Inventors

  • 👤 Masahito Yoshino

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 19:07
CPC Classifications
G; G04; G04C; G04C13/00; G04C13/08; G04C13/10; G04C13/11

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 168 words
In an electronic timepiece, a step motor having a permanent magnet rotor adapted to be stepped through a specific angle, at least two stator poles having semi-circular recessed portions, said recessed portions substantially surrounding said rotor at the periphery thereof, and an electromagnetic core coupled to said stator pole pieces said core including a coil wrapped therearound, said electromagnetic core being adapted in response to each drive pulse applied to said coil to effect first and second magnetic orientations of said stator poles in order to step said rotor through said specific angle, the improvement comprising means coupled to said coil for applying drive pulses thereto to effect said orientations; said drive pulse application means including short circuiting means for terminating said driving pulses applied to said coil at a time not later than the completion of the stepping of the rotor through said specific angle by short circuiting said coil wrapped around said core at a time not later than the terminating of the pulse applied thereto.
Claim 2
Dependent Claim 168 words
In an electronic timepiece, a step motor having a permanent magnet rotor adapted to be stepped through a specific angle, at least two stator poles having semi-circular recessed portions, said recessed portions substantially surrounding said rotor at the periphery thereof, and an electromagnetic core coupled to said stator pole pieces said core including a coil wrapped therearound, said electromagnetic core being adapted in response to each drive pulse applied to said coil to effect first and second magnetic orientations of said stator poles in order to step said rotor through said specific angle, the improvement comprising means coupled to said coil for applying drive pulses thereto to effect said orientations; said drive pulse application means including short circuiting means for terminating said driving pulses applied to said coil at a time not later than the completion of the stepping of the rotor through said specific angle by short circuiting said coil wrapped around said core at a time not later than the terminating of the pulse applied thereto.

References Cited (Backward Citations)

US2457637A Cited
US2601517A Cited
US2704334A Cited
US3375384A Cited
US3597915A Cited
US3657583A Cited
US3720864A Cited
US3731125A Cited
US3818690A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-07-13 1980-01-12 1980-07-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-07-13 1984-01-12 1984-07-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-07-13 1988-01-12 1988-07-13 $7700.00 Window Closed / Lapsed

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