US3878446A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current regulator for D.C. motors
Assignee: Unisys Corp
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Filing: 1973-03-29
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Granted: 1975-04-15
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Expires: 1993-03-29
Abstract
Abstract Disclosed is a circuit for regulating a d.c. motor that makes use of the inductive reactance of the motor and utilizes a switching regulator to regulate the current to the motor. This system has the advantage of allowing the transistors of the servo amplifier to be in either fully on or fully off condition thereby reducing the power dissipation within the amplifier.
Inventors
- 👤 Arnold W Brandt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:01
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; H02P7/291
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
122 words
A motor control circuit comprising: a bistable comparator circuit for comparing a single voltage representation of the motor current to a reference voltage; transistor switching means responsive to said bistable comparator circuit for connecting and disconnecting a power source to the motor; current bypass means for allowing the current generated by the inductive reactance of the motor to flow back through the motor when the power source has been disconnected; and feedback means, including a pair of series connected viarable resistors connected in series directly between said bistable comparator circuit and said motor, and a variable capacitor connected in common with said first and second variable resistors, for governing the switching rate of said bistable comparator circuit in accordance with the equation.
Claim 2
Dependent Claim
122 words
A motor control circuit comprising: a bistable comparator circuit for comparing a single voltage representation of the motor current to a reference voltage; transistor switching means responsive to said bistable comparator circuit for connecting and disconnecting a power source to the motor; current bypass means for allowing the current generated by the inductive reactance of the motor to flow back through the motor when the power source has been disconnected; and feedback means, including a pair of series connected viarable resistors connected in series directly between said bistable comparator circuit and said motor, and a variable capacitor connected in common with said first and second variable resistors, for governing the switching rate of said bistable comparator circuit in accordance with the equation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |