US3714537A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Limit control apparatus
Assignee: Honeywell Inc
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Filing: 1972-03-27
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Granted: 1973-01-30
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Expires: 1992-03-27
Abstract
Abstract A servo system includes a servo motor which drives a controlled member. The controlled member has a slider and actuating members thereon. The slider moves across a slide-wire and provides a feedback signal representative of the position of the controlled member. An amplifier receives an input signal, representative of a process variable, and the feedback signal, and generates a difference signal, representative of the difference therebetween, for driving the servo motor. The actuating members trip limit switches as the controlled member reaches predetermined limits of travel. The limit switches are serially connected in the servo motor circuit and each is shunted by a diode. The diode allows a difference signal to be applied to the servo motor after its associated limit switch has been tripped, only if the difference signal is of a polarity which would effect the movement of the controlled member away from the tripped limit switch.
Inventors
- 👤 P Bur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:21
CPC Classifications
G; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/16
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
135 words
In a servo system wherein a servo motor responds to first and second polarities of a control signal for moving a controlled member in first and second directions, respectively, between first and second limit positions. The combination comprising: a power circuit for applying said control signal to said servo motor, first switching means serially connected in said power circuit, first switch actuating means associated with said controlled member, said first switch actuating means being correlated to the movement of said controlled member to actuate said first switching means to a non-conductive condition upon movement of said controlled member to said first limit position, and first assymetrically conductive means connected in shunt with said first switching means for passing only control signals of a polarity tending to move said controlled member toward said second limit position.
Claim 2
Dependent Claim
135 words
In a servo system wherein a servo motor responds to first and second polarities of a control signal for moving a controlled member in first and second directions, respectively, between first and second limit positions. The combination comprising: a power circuit for applying said control signal to said servo motor, first switching means serially connected in said power circuit, first switch actuating means associated with said controlled member, said first switch actuating means being correlated to the movement of said controlled member to actuate said first switching means to a non-conductive condition upon movement of said controlled member to said first limit position, and first assymetrically conductive means connected in shunt with said first switching means for passing only control signals of a polarity tending to move said controlled member toward said second limit position.
Claim 3
Dependent Claim
135 words
In a servo system wherein a servo motor responds to first and second polarities of a control signal for moving a controlled member in first and second directions, respectively, between first and second limit positions. The combination comprising: a power circuit for applying said control signal to said servo motor, first switching means serially connected in said power circuit, first switch actuating means associated with said controlled member, said first switch actuating means being correlated to the movement of said controlled member to actuate said first switching means to a non-conductive condition upon movement of said controlled member to said first limit position, and first assymetrically conductive means connected in shunt with said first switching means for passing only control signals of a polarity tending to move said controlled member toward said second limit position.
Claim 4
Dependent Claim
135 words
In a servo system wherein a servo motor responds to first and second polarities of a control signal for moving a controlled member in first and second directions, respectively, between first and second limit positions. The combination comprising: a power circuit for applying said control signal to said servo motor, first switching means serially connected in said power circuit, first switch actuating means associated with said controlled member, said first switch actuating means being correlated to the movement of said controlled member to actuate said first switching means to a non-conductive condition upon movement of said controlled member to said first limit position, and first assymetrically conductive means connected in shunt with said first switching means for passing only control signals of a polarity tending to move said controlled member toward said second limit position.
Claim 5
Dependent Claim
43 words
The combination as set forth in claim 1 wherein said first switching means is a first limit switch, said first switch actuating means being a mechanical member mounted on said controlled member for mechanically actuating said first limit switch to said non-conductive condition.
Claim 6
Dependent Claim
19 words
The combination as set forth in claim 1 wherein said first assymetrically conduction means is a first diode means.
Claim 7
Dependent Claim
96 words
The combination as set forth in claim 1, and further including: second switching means serially connected in said power circuit; second switch actuating means associated with said controlled member, said second switch actuating means being correlated to the movement of said controlled member to actuate said second switching means to a non-conductive condition upon movement of said controlled member to said second limit position; and second assymetrically conductive means connected in shunt with said second switching means for passing only control signals of a polarity tending to move said controlled member toward said first limit position.
Claim 8
Dependent Claim
43 words
The combination as set forth in claim 4 wherein said second switching means is a second limit switch, said second switch actuating means being a mechanical member mounted on said controlled member for mechanically actuating said second limit switch to said non-conductive condition.
Claim 9
Dependent Claim
19 words
The combination as set forth in claim 4 wherein said second assymetrically conducting means is a second diode means.
Claim 10
Dependent Claim
193 words
A limit control apparatus comprising: input terminal means for receiving an input signal; a controlled member; a servo motor means for driving said controlled member; a measuring circuit for providing a feedback signal representative of the instantaneous position of said controlled member; a power means responsive to said input signal and said feedback signal for providing a control signal representative of the difference therebetween; power circuit for applying said control signal to said servo motor means, said servo motor being responsive to first and second polarities of said control signal for moving said controlled member in first and second directions, respectively, between first and second limit positions; first switching means serially connected in said power circuit; first switch actuating means associated with said controlled member, said first switch actuating means being corRelated to the movement of said controlled member to actuate said first switching means to a non-conductive condition upon movement of said first controlled member to said first limit position; and first assymetrically conductive means connected in shunt with said first switching means for passing only control signals of a polarity tending to move said controlled member toward said second limit position.
Claim 11
Dependent Claim
193 words
A limit control apparatus comprising: input terminal means for receiving an input signal; a controlled member; a servo motor means for driving said controlled member; a measuring circuit for providing a feedback signal representative of the instantaneous position of said controlled member; a power means responsive to said input signal and said feedback signal for providing a control signal representative of the difference therebetween; power circuit for applying said control signal to said servo motor means, said servo motor being responsive to first and second polarities of said control signal for moving said controlled member in first and second directions, respectively, between first and second limit positions; first switching means serially connected in said power circuit; first switch actuating means associated with said controlled member, said first switch actuating means being corRelated to the movement of said controlled member to actuate said first switching means to a non-conductive condition upon movement of said first controlled member to said first limit position; and first assymetrically conductive means connected in shunt with said first switching means for passing only control signals of a polarity tending to move said controlled member toward said second limit position.
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) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |