US4604576A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic delay line incorporated in a position detector for a movable nuclear reactor control rod
Assignee: GERIN MERLIN RUE HENRI TARZE
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Filing: 1983-03-10
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Granted: 1986-08-05
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Expires: 2003-03-10
Abstract
Abstract The invention concerns a position detector without mechanical contact. A permanent magnet attached to a mobile component co-operate with a sensor governed by the local action of the magnet. The sensor is constituted by an electromagnetic delay line having a saturable ferrite core onto which a winding propagating high frequency pulses is coiled. A reflectometer delivers the position indicator signal. The detector may be used to detect the position of a nuclear reactor control rod.
Inventors
- 👤 Michel R. Barrault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:08
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/043; G01; G01D; G01D5/00; G01D5/48; G01D5/485; G21; G21C; G21C17/00; G21C17/10; G21C17/12; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
160 words
A detection device for detecting the position of a movable nuclear reactor control rod, comprising: a permanent magnet attached to the movable control rod and slidable axially inside a non magnetic tube, a sensor governed by the local action of the permanent magnet for delivering a signal indicative of the position of the movable control rod, the sensor comprising an electromagnetic delay line located adjacent to and along the path of the magnet and including a rectilinear core of saturable magnetic material cooperating with a winding propagating high frequency pulses, a generator connected to the input of the delay line to emit high frequency pulses, measuring means for detecting local saturation of the core facing the permanent magnet, said saturation entailing a variation in the magnetic permeability of the core and a change in pulse propagation conditions in the winding, and processing means co-operating with the measuring means for generating a signal representative of the position of the control rod.
Claim 2
Dependent Claim
160 words
A detection device for detecting the position of a movable nuclear reactor control rod, comprising: a permanent magnet attached to the movable control rod and slidable axially inside a non magnetic tube, a sensor governed by the local action of the permanent magnet for delivering a signal indicative of the position of the movable control rod, the sensor comprising an electromagnetic delay line located adjacent to and along the path of the magnet and including a rectilinear core of saturable magnetic material cooperating with a winding propagating high frequency pulses, a generator connected to the input of the delay line to emit high frequency pulses, measuring means for detecting local saturation of the core facing the permanent magnet, said saturation entailing a variation in the magnetic permeability of the core and a change in pulse propagation conditions in the winding, and processing means co-operating with the measuring means for generating a signal representative of the position of the control rod.
Claim 3
Dependent Claim
37 words
A detection device according to claim 1, wherein the core of magnetic material and the associated winding are placed inside a hollow metal casing of non-magnetic electrically conducting material, so as to constitute a coaxial delay line.
Claim 4
Dependent Claim
32 words
A detection device according to claim 1, wherein the winding coiled on the core, co-operates with an adjacent conductor to form a two-wire delay line placed in a housing of insulating material.
Claim 5
Dependent Claim
74 words
A detection device according to claim 1, wherein the winding lies along the core through which it runs or onto which it is coiled, and that the said high frequency generator and measuring and processing means constitute a reflectometer connected to the delay line, the opposite end of the line being loaded by an impedance of predetermined value able to establish standing wave conditions with variable reflection depending on the position of the magnet.
Claim 6
Dependent Claim
60 words
A detection device according to claim 4, wherein the reflectometer is arranged to furnish the ratio of the outgoing and return time of a high frequency pulse reflected in the intermediate zone of the core saturated by the magnet to that of a high frequency pulse reflected at the end of the line, said ratio representing the position indicator signal.
Claim 7
Dependent Claim
35 words
A detection device according to claim 1, wherein the magnet cooperates with pole-pieces or a magnetic circuit so as to concentrate the magnetic flux in the saturable zone of the core situated facing the magnet.
Claim 8
Dependent Claim
36 words
A detection device according to claim 1, wherein the delay line is connected to an auxiliary generator able to inject contant or variable d.c. bias current into the winding to enhance the sensitivity of the sensor.
Claim 9
Dependent Claim
43 words
A detection device according to claim 1, comprising a rectilinear ferrite core, wherein the calibration of the sensor distance is achieved by dividing the core into several aligned elementary sections delimited either by zones saturated by means of auxiliary magnets or by discontinuities.
Claim 10
Dependent Claim
50 words
A detection device according to claim 2, wherein the core is hollow and formed by a single tube of ferrite or by several elementary tubes placed end to end along the axis of the metal casing and that the winding is constituted by a central conductor going through the core.
Claim 11
Dependent Claim
29 words
A detection device according to claim 9, wherein the inner and outer surfaces of each elementary tube of the ferrite core are coated by means of a metallic layer.
Claim 12
Dependent Claim
41 words
A detection device according to claim 2, wherein the rectilinear core is divided into several sections and that metal spacers are provided between the different sections of the core so as to extend radially close to the non-magnetic, electrically conducting casing.
Claim 13
Dependent Claim
41 words
A detection device according to claim 1, wherein said winding cooperates with a return circuit constituted by the tube housing the permanent magnet, so as to form a single wire delay line, said tube being of non-magnetic and electrically conducting material.
Claim 14
Dependent Claim
46 words
A detection device according to claim 1, wherein the measuring and processing means include a device which detects a variation in the reflection coefficient of the high frequency pulses emitted by said generator so as to deliver a signal representative of the position of the magnet.
Claim 15
Dependent Claim
43 words
A detection device according to claim 1, wherein the measuring and processing means include a device which detects a variation of the standing wave ratio of said electromagnetic delay line so as to generate a signal representative of the position of the magnet.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-08-04 | 1990-02-03 | 1990-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-04 | 1994-02-03 | 1994-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-04 | 1998-02-03 | 1998-08-05 | $7700.00 | Window Closed / Lapsed |