Patent US3873901A successfully refreshed from Google Patents.
US3873901A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic torque control system for motors
Assignee: Unisys Corp
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Filing: 1973-03-30
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Granted: 1975-03-25
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Expires: 1993-03-30
Abstract
Abstract Disclosed is circuit means for controlling the torque of the servo motor with respect to the speed of the servo motor. This system finds particular application in document feed apparatus where it is useful to maintain constant torque over a range of speeds. The control circuit includes a speed sensing element, switching elements and a servo amplifier for applying power to the servo motor. This system may also be adapted to compensate for the damping constant of the servo motor.
Inventors
- 👤 Jack Beery
- 👤 Arnold W Brandt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:47
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/2855; Y; Y10; Y10S; Y10S388/00; Y10S388/90; Y10S388/902; Y10S388/923; Y10S388/93
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
54 words
A torque control system for a servo motor comprising: speed sensing means; a servo amplifier for providing input voltage to the motor; and switching means responsive to said speed sensing means for switching the input to said servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current.
Claim 2
Dependent Claim
54 words
A torque control system for a servo motor comprising: speed sensing means; a servo amplifier for providing input voltage to the motor; and switching means responsive to said speed sensing means for switching the input to said servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current.
Claim 3
Dependent Claim
19 words
The torque control system of claim 1 wherein said speed sensing means includes a tachometer coupled to said motor.
Claim 4
Dependent Claim
49 words
The torque control system of claim 1 wherein said switch means comprises a switching amplifier and an electronic switch responsive to said switching amplifier and operative to switch the input of said servo amplifier from the voltage representing the motor voltage to the voltage representing the motor output current.
Claim 5
Dependent Claim
62 words
An improved motor control system for a document feed apparatus having a servo amplifier for providing input voltage to the motor wherein the improvement comprises: a speed sensing means; and a switching means responsive to said speed sensing means for switching the input to the servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current.
Claim 6
Dependent Claim
62 words
An improved motor control system for a document feed apparatus having a servo amplifier for providing input voltage to the motor wherein the improvement comprises: a speed sensing means; and a switching means responsive to said speed sensing means for switching the input to the servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current.
Claim 7
Dependent Claim
25 words
The improved motor control system of claim 4 wherein said switch means comprises: a switching amplifier; and an electronic switch responsive to said switching amplifier.
Claim 8
Dependent Claim
80 words
A torque control system foR a servo motor comprising: a servo amplifier for providing input voltage to the motor; speed sensing means; switching means responsive to said speed sensing means for switching the input to said servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current; and circuit means connected between said speed sensing means and said servo amplifier for inputting to said servo amplifier a voltage representing the speed of the motor.
Claim 9
Dependent Claim
80 words
A torque control system foR a servo motor comprising: a servo amplifier for providing input voltage to the motor; speed sensing means; switching means responsive to said speed sensing means for switching the input to said servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current; and circuit means connected between said speed sensing means and said servo amplifier for inputting to said servo amplifier a voltage representing the speed of the motor.
Claim 10
Dependent Claim
19 words
The torque control system of claim 6 wherein said speed sensing means is a tachometer coupled to the motor.
Claim 11
Dependent Claim
24 words
The torque control system of claim 6 wherein said switch means comprises: a switching amplifier; and an electronic switch responsive to said switching amplifier.
Claim 12
Dependent Claim
31 words
The torque control system of claim 8 wherein said switching amplifier includes adjustable resistive means for varying the response of said switching amplifier with respect to various speeds of the motor.
Claim 13
Dependent Claim
16 words
The torque control system of claim 6 wherein said circuit means includes at least one amplifier.
Claim 14
Dependent Claim
81 words
A torque control system for compensating for the damping constant of a servo motor comprising: a servo amplifier; speed sensing means; a switching circuit responsive to said speed sensing means for switching input to said servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current; a compensating circuit connected between said speed sensing circuit and said servo amplifier for providing an input signal to said servo amplifier proportional to the speed of the motor.
Claim 15
Dependent Claim
81 words
A torque control system for compensating for the damping constant of a servo motor comprising: a servo amplifier; speed sensing means; a switching circuit responsive to said speed sensing means for switching input to said servo amplifier from a voltage representing the motor voltage to a voltage representing the motor output current; a compensating circuit connected between said speed sensing circuit and said servo amplifier for providing an input signal to said servo amplifier proportional to the speed of the motor.
Claim 16
Dependent Claim
26 words
The torque control system of claim 11 wherein said compensating means includes amplifier means with a gain substantially equal to the damping constant of the motor.
Claim 17
Dependent Claim
54 words
A control system for maintaining the torque output of a motor constant over a range of speeds of the motor, comprising: a servo amplifier; speed sensing means; and circuit means connected to said speed sensing circuit and said servo amplifier for inputting a signal to said servo amplifier representing the speed of the motor.
Claim 18
Dependent Claim
54 words
A control system for maintaining the torque output of a motor constant over a range of speeds of the motor, comprising: a servo amplifier; speed sensing means; and circuit means connected to said speed sensing circuit and said servo amplifier for inputting a signal to said servo amplifier representing the speed of the motor.
Claim 19
Dependent Claim
15 words
The control system of claim 13 wherein said circuit means includes at least one amplifier.
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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |