US3748560A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device including thyristor chopper for controlling inductive load
Assignee: Fuji Electric Co Ltd
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Filing: 1972-07-14
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Granted: 1973-07-24
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Expires: 1992-07-14
Abstract
Abstract A control device including a thyristor chopper for controlling an inductive load such as a d.c. motor comprises a chopper including a main thyristor and means for extingushing the main thyristor, the chopper being connected in series or in parallel to a d.c. power source, a free-wheeling diode or a normal current blocking diode, either of which is of a polarity opposite to that of the d.c. power source and is connected in parallel or in series to the inductive load, and an auxiliary circuit comprising a resistor and a second thyristor connected in series and further connected in parallel to the free-wheeling diode or normal current blocking diode, the second thyristor having a polarity reverse to that of the diode, and receiving, at least in the starting period of the controlling operation, an ignition pulse in synchronism with the ignition pulse applied to the main thyristor, and the resistance value of the resistor being so selected that the current flowing through the main thyristor is greater than a latching current of the main thyristor.
Inventors
- 👤 K Sawa
- 👤 S Kinoshita
- 👤 M Kaimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:59
CPC Classifications
H; H02; H02P; H02P3/00; H02P3/06; H02P3/08; H02P3/14; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/125; H02M3/135; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
156 words
A control device including a thyristor chopper for controlling an inductive load, comprising a chopper including a main thyristor and means for extingushing the main thyristor and connected with series to the inductive load and also to a d.c. power source, a free-wheeling diode connected in parallel with said inductive load, and an auxiliary circuit comprising a resistor and a second thyristor connected in series and further connected in parallel with said free-wheeling diode, said second thyristor having a polarity reverse to that of the free-wheeling diode and receiving, at least in the starting period of the controlling operation, an ignition pulse in synchronism with an ignition pulse applied to the main thyristor, and the resistance value of said resistor being so selected that the current flowing from the d.c. power source to the resistor and the second thyristor and passing through the main thyristor is greater than the latching curreNt value of the main thyristor.
Claim 2
Dependent Claim
156 words
A control device including a thyristor chopper for controlling an inductive load, comprising a chopper including a main thyristor and means for extingushing the main thyristor and connected with series to the inductive load and also to a d.c. power source, a free-wheeling diode connected in parallel with said inductive load, and an auxiliary circuit comprising a resistor and a second thyristor connected in series and further connected in parallel with said free-wheeling diode, said second thyristor having a polarity reverse to that of the free-wheeling diode and receiving, at least in the starting period of the controlling operation, an ignition pulse in synchronism with an ignition pulse applied to the main thyristor, and the resistance value of said resistor being so selected that the current flowing from the d.c. power source to the resistor and the second thyristor and passing through the main thyristor is greater than the latching curreNt value of the main thyristor.
Claim 3
Dependent Claim
168 words
A control device including a thyristor chopper for controlling an inductive load consisting of a d.c. motor, comprising a chopper including a main thyristor and means for extingushing the main thyristor and connected in parallel with said d.c. motor and also to a d.c. power source, a normal current blocking diode connected in series with said d.c. power source, and an auxiliary circuit comprising a resistor and a second thyristor connected in series and further connected in parallel with said normal current blocking diode, said second thyristor having a polarity reverse to that of the normal current blocking diode and receiving, at least in the starting period of a regenerative mode of operation, an ignition pulse in synchronism with an ignition pulse applied to the main thyristor, and the resistance value of said resistor being so selected that the current flowing from the d.c. power source to the resistor through the main thyristor and the second thyristor is greater than the latching current value of the main thyristor.
Claim 4
Dependent Claim
168 words
A control device including a thyristor chopper for controlling an inductive load consisting of a d.c. motor, comprising a chopper including a main thyristor and means for extingushing the main thyristor and connected in parallel with said d.c. motor and also to a d.c. power source, a normal current blocking diode connected in series with said d.c. power source, and an auxiliary circuit comprising a resistor and a second thyristor connected in series and further connected in parallel with said normal current blocking diode, said second thyristor having a polarity reverse to that of the normal current blocking diode and receiving, at least in the starting period of a regenerative mode of operation, an ignition pulse in synchronism with an ignition pulse applied to the main thyristor, and the resistance value of said resistor being so selected that the current flowing from the d.c. power source to the resistor through the main thyristor and the second thyristor is greater than the latching current value of the main thyristor.
Claim 5
Dependent Claim
284 words
A control device including a thyristor chopper for controlling an inductive load consisting of a d.c. motor, comprising: a load circuit consisting of a d.c. motor having an armature and a series connected field winding and switching means for switching the polarity of the armature; a chopper comprising a main thyristor and means for extinguishing the main thyristor and connected between one terminal of said load circuit and one terminal of a d.c. power source; first switching means connected between the other terminal of said load circuit and the other terminal of said d.c. power source, said switching means being closed during normal operation of the d.c. motor and opened during regenerative braking operation of the same motor; second switching means connected parallelly with said series connected load circuit and chopper, said switching means being opened during normal operation of the d.c. motor and closed during regenerative braking operation of the same motor; a diode of a polarity reverse to that of the d.c. power source connected in parallel with the series connected load circuit and the first switching means; and a second thyristor and a resistor connected in series and further connected in parallel with said diode, the polarity of said second thyristor being reverse to that of the diode, said second thyristor receiving, at least in the starting period of the normal operation and the regenerative braking operation, an ignition pulse synchronized with an ignition pulse applied to the main thyristor, and the resistance value of said resistor being so selected that the current flowing from the d.c. power source to the resistor through the main thyristor and the second thyristor is greater than the latching current value of the main thyristor.
Claim 6
Dependent Claim
284 words
A control device including a thyristor chopper for controlling an inductive load consisting of a d.c. motor, comprising: a load circuit consisting of a d.c. motor having an armature and a series connected field winding and switching means for switching the polarity of the armature; a chopper comprising a main thyristor and means for extinguishing the main thyristor and connected between one terminal of said load circuit and one terminal of a d.c. power source; first switching means connected between the other terminal of said load circuit and the other terminal of said d.c. power source, said switching means being closed during normal operation of the d.c. motor and opened during regenerative braking operation of the same motor; second switching means connected parallelly with said series connected load circuit and chopper, said switching means being opened during normal operation of the d.c. motor and closed during regenerative braking operation of the same motor; a diode of a polarity reverse to that of the d.c. power source connected in parallel with the series connected load circuit and the first switching means; and a second thyristor and a resistor connected in series and further connected in parallel with said diode, the polarity of said second thyristor being reverse to that of the diode, said second thyristor receiving, at least in the starting period of the normal operation and the regenerative braking operation, an ignition pulse synchronized with an ignition pulse applied to the main thyristor, and the resistance value of said resistor being so selected that the current flowing from the d.c. power source to the resistor through the main thyristor and the second thyristor is greater than the latching current value of the main thyristor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |