Patent US4490663A successfully refreshed from Google Patents.
US4490663A
Expired / Lapsed
US
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Device for driving a stepping motor
Assignee: Mikuni Corp
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Filing: 1982-06-28
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Granted: 1984-12-25
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Expires: 2002-06-28
Abstract
Abstract A device for driving a stepping motor for use in a vehicle is disclosed. The device comprises a plurality of phase coils, a switching means connected to the phase coils, a pulse distributor circuit connected to the switching means for generating control signals thereby controlling the ON or OFF state of the switching means, a connection means for connecting the phase coils to a power supply source, and a current sustaining means connected between the connection means and the phase coils in common therewith.
Inventors
- 👤 Shuichi Kamiyama
- 👤 Yoji Okada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:05
CPC Classifications
H; H02; H02P; H02P8/00; H02P8/12
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
198 words
A circuit for driving a stepping motor, comprising: a power supply source, a plurality of phase coils, each having a respective inductance L m , a switching transistor connected to each said phase coil, each said transistor having an emitter and a control electrode, a regulatory resistor having a resistance R c connected to the emitter of each said switching transistor, a pulse distributing circuit connected to supply ON and OFF signals to the control electrodes of the switching transistors, said pulse distributing circuit having a pulse period T p , current holding means connecting the phase coils to said power supply source and comprising a resistance R and an inductance L c in series, L c being much larger than L m , and provding for each said phase coil a total inductance L=L m +L c which changes little when the coil is switched ON and OFF, so that the coil's time constant L/R is larger than T p while the time constant L m /R c is smaller than T p and smaller than L/R, so that the time constant L/R is always larger compared with T p , even at the highest operating speed.
Claim 2
Dependent Claim
198 words
A circuit for driving a stepping motor, comprising: a power supply source, a plurality of phase coils, each having a respective inductance L m , a switching transistor connected to each said phase coil, each said transistor having an emitter and a control electrode, a regulatory resistor having a resistance R c connected to the emitter of each said switching transistor, a pulse distributing circuit connected to supply ON and OFF signals to the control electrodes of the switching transistors, said pulse distributing circuit having a pulse period T p , current holding means connecting the phase coils to said power supply source and comprising a resistance R and an inductance L c in series, L c being much larger than L m , and provding for each said phase coil a total inductance L=L m +L c which changes little when the coil is switched ON and OFF, so that the coil's time constant L/R is larger than T p while the time constant L m /R c is smaller than T p and smaller than L/R, so that the time constant L/R is always larger compared with T p , even at the highest operating speed.
Claim 3
Dependent Claim
21 words
A circuit for driving a stepping motor as claimed in claim 1, wherein the current holding means is a choke coil.
References Cited (Backward Citations)
US3826966A
Cited
US4140955A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |