US3890607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic position indicator
Assignee: Merlin Gerin SA
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Filing: 1973-01-17
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Granted: 1975-06-17
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Expires: 1993-01-17
Abstract
Abstract An electromagnetic position indicator to continuously indicate the position of a linearly movable mobile, such as a nuclear reactor control rod, operatively connected to magnetic core means which vary the inductive coupling between primary and secondary windings. One of the windings, preferably the secondary winding comprises pairs of oppositely connected coils spaced apart in the direction of movement of the core means to improve the measurement precision. Analog or digital means may be provided to process the output signal.
Inventors
- 👤 Yves Pelenc
- 👤 Jean Ambier
- 👤 Roger Lavergne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 01:48
CPC Classifications
G; G21; G21C; G21C17/00; G21C17/10; G21C17/12; G01; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/20; G01D5/22; G01D5/225; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
165 words
An electromagnetic position indicator comprising: a. inductively coupled primary and secondary winding means extending along a linear path, said secondary winding means comprising a plurality of pairs of series-connected differential coils spaced along said path, b. an elongated magnetic core having a head end movable along said path, the number of coils linked with said core varying with the position of said core, c. means for coupling an alternating current source to said primary winding, the application of said alternating current source to said primary winding subjecting the pairs of differential coils having a coil disposed in the immediate proximity of the head end of said core to magnetic imbalance and producing at the terminals thereof a net non-zero output signal, the remaining pairs of coils being magnetically balanced to produce at the terminals thereof a substantially zero output signal, and d. circuit means connected to the terminals of all pairs of said coils to deliver a signal representative of the position of said core.
Claim 2
Dependent Claim
165 words
An electromagnetic position indicator comprising: a. inductively coupled primary and secondary winding means extending along a linear path, said secondary winding means comprising a plurality of pairs of series-connected differential coils spaced along said path, b. an elongated magnetic core having a head end movable along said path, the number of coils linked with said core varying with the position of said core, c. means for coupling an alternating current source to said primary winding, the application of said alternating current source to said primary winding subjecting the pairs of differential coils having a coil disposed in the immediate proximity of the head end of said core to magnetic imbalance and producing at the terminals thereof a net non-zero output signal, the remaining pairs of coils being magnetically balanced to produce at the terminals thereof a substantially zero output signal, and d. circuit means connected to the terminals of all pairs of said coils to deliver a signal representative of the position of said core.
Claim 3
Dependent Claim
58 words
A position indicator according to claim 1 wherein said secondary winding means comprises a plurality of coils which are series-connected in a plurality of groups corresponding to the number of bits of A binary code, said groups delivering at the terminals thereof net output signals for conversion into binary signals, said signals indicating the position of said core.
Claim 4
Dependent Claim
22 words
A position indicator according to claim 1, said circuit means comprising logic circuit means converting said differential output signals into binary signals.
Claim 5
Dependent Claim
20 words
A position indicator according to claim 3, said logic circuit means comprising discriminating circuit means actuating an electronic gate means.
Claim 6
Dependent Claim
37 words
A position indicator according to claim 4, the output terminals of said electronic gate means being connected to respective points of a voltage divider delivering an output signal varying steadily with the distance covered by said core.
Claim 7
Dependent Claim
38 words
A position indicator according to claim 5, each of said pairs of secondary coils being connected to a discriminating trigger circuit actuating an electronic gate, the different electronic gates being connected to sequential points of a voltage divider.
Claim 8
Dependent Claim
32 words
A position indicator according to claim 6, the threshold values of said discriminating trigger circuits being set in such a manner that at most two adjacent gates are opened at a time.
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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |