US3760249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coarse-fine analog positioning system
Assignee: Westinghouse Electric Corp
•
Filing: 1971-03-30
•
Granted: 1973-09-18
•
Expires: 1991-03-30
Abstract
Abstract An accurate closed loop analog positioning system utilizing a linear sensor of the type employing a magnetic sensing element and a balance coil which acts basically as a transformer so as to eliminate direct current drift which is prevalent in most analog positioning systems. The magnetic sensing element is preferably mounted on the periphery of a disc of insulating material geared to a machine part which travels along a linear path of travel such that the disc will rotate through less than one complete revolution as the machine part moves from one end of its path of travel to the other. By causing the sensing element to rotate to a position where it is directly opposite the balance coil, the drive motor driving the machine part can be made to slow down and stop at that exact point.
Inventors
- 👤 J Connors
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:04
CPC Classifications
G; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/18; G05D3/1445
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
204 words
In a system of the type wherein an element is driven along a fixed essentially linear path of travel by a drive motor, the combination of a rotary member mechanically coupled to said element such that movement of the element along its entire path of travel will cause the rotary member to rotate through no more than one revolution, a magnetic element carried by said rotary member at one point about its periphery, control circuitry including balance coil means positioned adjacent a point in the rotary path of travel of said magnetic element on said rotary member and adapted to produce an output signal which approaches zero when said magnetic element is moved toward said coil means, means including a speed con-troller feeding into a current controller for normally con-trolling said motor at a speed determined by a speed reference signal applied to said speed controller, and switch means automatically actuated when said magnetic element approaches said balance coil means for disconnecting said speed controller from said current controller and for connecting said control circuitry to the current controller, whereby as said output signal approaches zero said element will be caused to decelerate and stop with said magnetic element adjacent said balance coil means.
Claim 2
Dependent Claim
204 words
In a system of the type wherein an element is driven along a fixed essentially linear path of travel by a drive motor, the combination of a rotary member mechanically coupled to said element such that movement of the element along its entire path of travel will cause the rotary member to rotate through no more than one revolution, a magnetic element carried by said rotary member at one point about its periphery, control circuitry including balance coil means positioned adjacent a point in the rotary path of travel of said magnetic element on said rotary member and adapted to produce an output signal which approaches zero when said magnetic element is moved toward said coil means, means including a speed con-troller feeding into a current controller for normally con-trolling said motor at a speed determined by a speed reference signal applied to said speed controller, and switch means automatically actuated when said magnetic element approaches said balance coil means for disconnecting said speed controller from said current controller and for connecting said control circuitry to the current controller, whereby as said output signal approaches zero said element will be caused to decelerate and stop with said magnetic element adjacent said balance coil means.
Claim 3
Dependent Claim
38 words
The system of claim 1 wherein said control circuitry includes an integrating operational amplifier connected to said balance coil means, the switch means being adapted to connect the output of said integrating operational amplifier to said current controller.
Claim 4
Dependent Claim
14 words
The system of claim 1 wherein said rotary member is formed from insulating material.
Claim 5
Dependent Claim
31 words
The system of claim 1 wherein said output signal, when said switch means is actuated, is linear and proportional to the relative displacement of said element from said balance coil means.
Claim 6
Dependent Claim
33 words
The system of claim 1 including electrical circuitry for varying the point at which said element will stop in its path of travel with said magnetic element being adjacent the balance coil means.
Claim 7
Dependent Claim
54 words
The system of claim 5 wherein said electrical circuitry includes a selsyn transmitter connected to said driven element, a differential selsYn provided with a drive motor and connected to the output of said selsyn transmitter, and a selsyn receiver connected to the output of said differential selsyn and mechanically connected to said magnetic element.
References Cited (Backward Citations)
US2415819A
Cited
US2088659A
Cited
US2730664A
Cited
US2926345A
Cited
US2825859A
Cited
US3010063A
Cited
US3011113A
Cited
US3151282A
Cited
US3467900A
Cited
US3382422A
Cited
US3477027A
Cited
US3498093A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |