US3906319A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Universal motor speed control system
Assignee: Individual
•
Filing: 1973-10-04
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Granted: 1975-09-16
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Expires: 1993-10-04
Abstract
Abstract A motor speed control system in which pulse signals with controlled gradually increasing amplitude levels are applied to a motor to maintain it at a desired speed under variable loading conditions. The system is suitable for controlling the speed of a wide variety of motors and is particularly advantageous for low inertia motors.
Inventors
- 👤 Lee J Milligan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:58
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/288; H02P7/2885; H02P23/00; H02P23/22; Y; Y10; Y10S; Y10S388/00; Y10S388/90; Y10S388/902; Y10S388/903; Y10S388/907; Y10S388/912
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
68 words
A system for controlling the speed of a motor, comprising means for generating an error signal indicative of a departure of the motor from a specified speed condition, and means responsive to the error signal for producing a plurality of increasing discrete and different drive levels during the time when the motor speed is below said specified speed, and means for applying said drive levels to said motor.
Claim 2
Independent Claim
68 words
A system for controlling the speed of a motor, comprising means for generating an error signal indicative of a departure of the motor from a specified speed condition, and means responsive to the error signal for producing a plurality of increasing discrete and different drive levels during the time when the motor speed is below said specified speed, and means for applying said drive levels to said motor.
Claim 3
Dependent Claim
50 words
A motor speed control system in accordance with claim 1 wherein the error signal generated means comprises means for representing a desired condition of the motor, means for representing the actual condition of said motor, and means for comparing the representations of the desired and actual conditions of the motor.
Claim 4
Dependent Claim
60 words
A motor speed control system in accordance with claim 1 wherein the drive level applying means comprises a power transducer having a control terminal connected to the producing means, an input terminal connectable to a power source, and an output terminal connectable to said motor, and means for applying a bias voltage at the output terminal of said power transducer.
Claim 5
Dependent Claim
36 words
a motor speed control system in accordance with claim 1 wherein the producing means comprises means for generating staircase pulse signals, and means for isolating the stepped pulse signals from the pulse drive level applying means.
Claim 6
Dependent Claim
18 words
A motor speed control system in accordance with claim 4 wherein the isolating means comprises a field-effect transistor.
Claim 7
Dependent Claim
27 words
A motor speed control system in accordance with claim 4 wherein the staircase signal generating means comprises means for generating a stepped wave with successively decreasing steps.
Claim 8
Dependent Claim
40 words
A motor speed control system in accordance with claim 6 wherein the staircase signal generating means comprises means for generating successive pulse signals which appear on successive control leads and are applied to the isolating means during selected error intervals.
Claim 9
Dependent Claim
29 words
A motor speed control system in accordance with claim 6 wherein the staircase signal generating means includes means for controlling the maximum number of steps in said stepped wave.
Claim 10
Dependent Claim
33 words
A motor speed control system in accordance with claim 7 wherein the means for generating successive pulse signals includes a counter connected to said error signal and a decoder connected to said counter.
Claim 11
Dependent Claim
25 words
A motor speed control system in accordance with claim 8 wherein the step control means includes means connected to a decoder for inhibiting a counter.
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) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |