US3742328A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Closed loop stepping motor servo mechanism
Assignee: Yokogawa Electric Corp
•
Filing: 1971-04-28
•
Granted: 1973-06-26
•
Expires: 1991-04-28
Abstract
Abstract A servo - mechanism utilizing a pulse motor comprises a comparator amplifier for producing an output corresponding to the difference between an input signal voltage and a feedback voltage, a signal conversion circuit for converting the output from the comparator amplifier into two bit level signals, and a pulse motor driving circuit for controlling the direction of the pulse motor in accordance with one of the two bit level signals and for controlling the start and stop of the pulse motor in accordance with the other of the two bit level signals.
Inventors
- 👤 S Ohta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:38
CPC Classifications
G; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/18; G05D3/183
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
314 words
A servo-mechanism for driving a pulse motor including a comparator amplifier for producing an output corresponding to the difference between an input signal voltage and a feedback voltage, a circuit for driving said pulse motor in accordance with the output of the said comparator amplifier, and circuit means for producing said feedback voltage by the rotation of the said pulse motor in order to attain a rotation angle of the said pulse motor corresponding to the input signal voltage, thereby balancing said feedback voltage and said input signal voltage, in which: said comparator amplifier comprises a linear integrated circuit amplifier with differential input, a single direct electric current source connected to supply the source terminal of said integrated circuit amplifier, and a bias voltage attained from said single direct electric current source applied to be the base electric potential level for operation of said integrated circuit amplifier; and said circuit means for producing said feedback voltage comprises a magnetic convertor having a magnetic core wound with an exciting coil, a detection coil and a feedback coil, and a movable permanent magnet which is displaced by said pulse motor, means including a tuned amplifier for amplifying the output signal at said detection coil, for applying the half wave alternate output of the said tuned amplifier as positive feedback to said feedback coil to form a self-oscillating tuned amplifier circuit in order to attain an output voltage corresponding to the degree of displacement of the said movable permanent magnet, Means responsive to said output voltage and operative to apply a negative feedback current to said feedback coil in accordance with the rectified output voltage of said selfoscillating tuned amplifier for balancing the magnetic flux from said movable permanent magnet, and means for developing said feedback voltage from said feedback current and applying said feedback voltage in opposition to said input signal voltage at said differential input.
Claim 2
Dependent Claim
314 words
A servo-mechanism for driving a pulse motor including a comparator amplifier for producing an output corresponding to the difference between an input signal voltage and a feedback voltage, a circuit for driving said pulse motor in accordance with the output of the said comparator amplifier, and circuit means for producing said feedback voltage by the rotation of the said pulse motor in order to attain a rotation angle of the said pulse motor corresponding to the input signal voltage, thereby balancing said feedback voltage and said input signal voltage, in which: said comparator amplifier comprises a linear integrated circuit amplifier with differential input, a single direct electric current source connected to supply the source terminal of said integrated circuit amplifier, and a bias voltage attained from said single direct electric current source applied to be the base electric potential level for operation of said integrated circuit amplifier; and said circuit means for producing said feedback voltage comprises a magnetic convertor having a magnetic core wound with an exciting coil, a detection coil and a feedback coil, and a movable permanent magnet which is displaced by said pulse motor, means including a tuned amplifier for amplifying the output signal at said detection coil, for applying the half wave alternate output of the said tuned amplifier as positive feedback to said feedback coil to form a self-oscillating tuned amplifier circuit in order to attain an output voltage corresponding to the degree of displacement of the said movable permanent magnet, Means responsive to said output voltage and operative to apply a negative feedback current to said feedback coil in accordance with the rectified output voltage of said selfoscillating tuned amplifier for balancing the magnetic flux from said movable permanent magnet, and means for developing said feedback voltage from said feedback current and applying said feedback voltage in opposition to said input signal voltage at said differential input.
Claim 3
Dependent Claim
68 words
The servo-mechanism according to claim 1, arranged for common mode suppression wherein said comparator amplifier has said input signal voltage applied between its differential inputs, said feedback voltage is applied to only one of said differential inputs, and said bias voltage is applied to said one differential input, and means for applying the output of said comparator amplifier as negative feedback to the other of its differential inputs.
Claim 4
Dependent Claim
115 words
The servo-mechanism, according to claim 1, and further including a signal conversion circuit for converting the output of said comparator amplifier into two bit level signals, a circuit for generating a two phase rectangular wave signal whose relative phase is controlled in accordance with one of said two bit level signals, a gate circuit controlled in accordance with the other one of said two bit level signals, and wherein said circuit for driving said pulse motor is responsive to said relative phase of said two phase rectangular wave signal for controlling the direction of rotation of said pulse motor and responsive to said gate circuit for controlling the start and stop of said pulse motor.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |