US3573589A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Position servo system for a motor including detenting at destination
Assignee: Unisys Corp
•
Filing: 1969-04-01
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Granted: 1971-04-06
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Expires: 1989-04-01
Abstract
Abstract The disclosure embodies a servo system to position a rotatable print wheel with any one of a number of selectable printing type at a print line. The system includes a reversible electric step motor having a number of pulsable induction coils to rotate the print wheel. Selections of print wheel positions are effected by signals from keyboard actuated switches and the position selected is indicated by a position indicator which is driven by the step motor synchronously with the print wheel. A comparator receives and compares the signals from the keyboard actuated switches with signals from the position indicator to determine the angular displacement between the selected position and present position of the print wheel. Through digital logic systems including a pulse generator and a direction selection means, the number of pulses supplied to the motor to position the print wheel is effected along with the rotational driving of the wheel in the direction requiring least angular displacement of the wheel to reach the selected position. During the positioning of the print wheel, a control member responds to a match between the keyboard selected position and the position indicator to dynamically brake the step motor by simultaneously energizing all of the induction coils.
Inventors
- 👤 Jack Berry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:18
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/27; G05B19/29; G05B19/291; G05B2219/00; G05B2219/30; G05B2219/37; G05B2219/37297; G05B2219/42; G05B2219/42212
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
195 words
A servocontrol system for selectively positioning a print member said system comprising: a magnetic rotor operatively connected to the print member; a plurality of separately energizable induction coils arranged about the axis of said rotor, said coils consecutively energized to rotate said rotor; a plurality of control members electrically connected to each of said coils respectively controlling the energizing thereof; position indicator means operatively connected to said rotor to indicate the present position of said rotor, and the print member; indexing means to electrically select another position of the print member; comparator means operatively connected to said position indicator means and said indexing means to determine both the direction of rotation of said rotor and the amount of angular displacement of said rotor; pulse generating means responsive to said comparator means and operative to supply the correct number of pulses to said control members to effect the desired angular displacement of said rotor; and electrical dampening control means responsive to said comparator and operable to apply a voltage to each nonenergized induction coil at the selected position of the print member to stop rotation of said rotor and hold said rotor in the selected position.
Claim 2
Dependent Claim
195 words
A servocontrol system for selectively positioning a print member said system comprising: a magnetic rotor operatively connected to the print member; a plurality of separately energizable induction coils arranged about the axis of said rotor, said coils consecutively energized to rotate said rotor; a plurality of control members electrically connected to each of said coils respectively controlling the energizing thereof; position indicator means operatively connected to said rotor to indicate the present position of said rotor, and the print member; indexing means to electrically select another position of the print member; comparator means operatively connected to said position indicator means and said indexing means to determine both the direction of rotation of said rotor and the amount of angular displacement of said rotor; pulse generating means responsive to said comparator means and operative to supply the correct number of pulses to said control members to effect the desired angular displacement of said rotor; and electrical dampening control means responsive to said comparator and operable to apply a voltage to each nonenergized induction coil at the selected position of the print member to stop rotation of said rotor and hold said rotor in the selected position.
Claim 3
Dependent Claim
51 words
The servocontrol system according to claim 1 wherein the electrical dampening control means selectively and electrically connects to each inductive coil adjacent to the presently energized inductive coil at said selected position a voltage to stop the rotation of said rotor and to hold the said rotor in said selected position.
Claim 4
Dependent Claim
31 words
The servocontrol system according to claim 2 wherein said electrical dampening control means applies a reduced dampening voltage to said adjacent induction coils, when said rotor is in said selected position.
Claim 5
Dependent Claim
34 words
The servocontrol system according to claim 1 further including time delay means to remove the voltage from the previously nonenergized coils after the rotor has been in said selected position for a predetermined time.
Claim 6
Dependent Claim
35 words
The servocontrol system according to claim 1 wherein the electrical dampening control means is a switch member electrically connecting each of said nonenergized induction coils to a reduced voltage source to partially energize said coils.
Claim 7
Dependent Claim
137 words
A servocontrol system for positioning a magnetic rotor in any selected one of a number of angularly displaced positions comprising: a plurality of induction coils arrangeable about the axis of the rotor to be pulsed consecutively to rotate the rotor; selectively operable means to electrically select another position of displacement of the rotor from a previously selected position; a pulse generator operable to effect a signal representative of said previously selected position; a position control member responsive to said selective means and to said pulse generator and operable to control the number of pulses applied to said induction coils to effect the selected displacement of the rotor; and a control member responsive to said position control member and operable to effect energization of all of said coils to stop and hold the rotor in the selected position.
Claim 8
Dependent Claim
137 words
A servocontrol system for positioning a magnetic rotor in any selected one of a number of angularly displaced positions comprising: a plurality of induction coils arrangeable about the axis of the rotor to be pulsed consecutively to rotate the rotor; selectively operable means to electrically select another position of displacement of the rotor from a previously selected position; a pulse generator operable to effect a signal representative of said previously selected position; a position control member responsive to said selective means and to said pulse generator and operable to control the number of pulses applied to said induction coils to effect the selected displacement of the rotor; and a control member responsive to said position control member and operable to effect energization of all of said coils to stop and hold the rotor in the selected position.
References Cited (Backward Citations)
US2827602A
Cited
US2864044A
Cited
US2989680A
Cited
US3374410A
Cited
US3465217A
Cited
US3385984A
Cited
US3466520A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-05 | 1974-10-05 | 1975-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-05 | 1978-10-05 | 1979-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-05 | 1982-10-05 | 1983-04-06 | $7700.00 | Window Closed / Lapsed |