US4053355A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nuclear reactor remote disconnect control rod coupling indicator
Assignee: Energy Research and Development Administration ERDA
•
Filing: 1975-10-14
•
Granted: 1977-10-11
•
Expires: 1995-10-14
Abstract
Abstract A coupling indicator for use with nuclear reactor control rod assemblies which have remotely disengageable couplings between the control rod and the control rod drive shaft. The coupling indicator indicates whether the control rod and the control rod drive shaft are engaged or disengaged. A resistive network, utilizing magnetic reed switches, senses the position of the control rod drive mechanism lead screw and the control rod position indicating tube, and the relative position of these two elements with respect to each other is compared to determine whether the coupling is engaged or disengaged.
Inventors
- 👤 Michael Vuckovich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 01:50
CPC Classifications
G; G21; G21C; G21C7/00; G21C7/06; G21C7/08; G21C7/12; G01; G01D; G01D5/00; G01D5/12; G01D5/25; G01D5/251; G01D5/2515; G21C17/00; G21C17/10; G21C17/12; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
302 words
A coupling indicator system for use with remotely disengageable control rod assemblies wherein the connection of an elongated control rod to an elongated control rod drive shaft is dependent upon the longitudinal axial position of a plunger, one position of said plunger creating coupling between said control rod and said drive shaft, and a second position of said plunger creating uncoupling between said control rod and said drive shaft, said control rod assembly including a control rod drive means, movable along the drive shaft longitudinal axis, for axially moving said drive shaft along the drive shaft longitudinal axis, said coupling indicator system comprising: means for determining the axial position of said plunger; means for determining the axial position of said drive means; and means for comparing the axial position of said plunger with respect to the axial position of said drive means, said means for determining the axial position of said plunger comprising: an elongated position indicator tube fixedly secured to and axially movable with, said plunger; a position indicator magnet secured to said position indicator tube; a plurality of equal resistances serially connected and having a first end point and a second end point; a common node; a plurality of normally non-conducting magnetically actuated switches parallelly connected between said resistances and said common node, one of said magnetically actuated switches being connected between each pair of adjacent resistances, said magnetically actuated switches being located such that at least one magnetically actuated switch is in magnetic communication with said position indicator magnet to cause such switch to conduct electric current; a first current source having a first electrical polarity serially connected to said plurality of resistances at said first end point; and means for measuring the voltage generated between said first current source and said common node to obtain a first voltage.
Claim 2
Dependent Claim
302 words
A coupling indicator system for use with remotely disengageable control rod assemblies wherein the connection of an elongated control rod to an elongated control rod drive shaft is dependent upon the longitudinal axial position of a plunger, one position of said plunger creating coupling between said control rod and said drive shaft, and a second position of said plunger creating uncoupling between said control rod and said drive shaft, said control rod assembly including a control rod drive means, movable along the drive shaft longitudinal axis, for axially moving said drive shaft along the drive shaft longitudinal axis, said coupling indicator system comprising: means for determining the axial position of said plunger; means for determining the axial position of said drive means; and means for comparing the axial position of said plunger with respect to the axial position of said drive means, said means for determining the axial position of said plunger comprising: an elongated position indicator tube fixedly secured to and axially movable with, said plunger; a position indicator magnet secured to said position indicator tube; a plurality of equal resistances serially connected and having a first end point and a second end point; a common node; a plurality of normally non-conducting magnetically actuated switches parallelly connected between said resistances and said common node, one of said magnetically actuated switches being connected between each pair of adjacent resistances, said magnetically actuated switches being located such that at least one magnetically actuated switch is in magnetic communication with said position indicator magnet to cause such switch to conduct electric current; a first current source having a first electrical polarity serially connected to said plurality of resistances at said first end point; and means for measuring the voltage generated between said first current source and said common node to obtain a first voltage.
Claim 3
Dependent Claim
43 words
The coupling indicator system according to claim 1 wherein a drive means magnet is secured to said drive means; and said means for determining the axial position of said drive means comprises means for determining the axial position of said drive means magnet.
Claim 4
Dependent Claim
81 words
The coupling indicator system according to claim 2 wherein said means for determining the axial position of said drive means magnet comprises: a second current source having a second electrical polarity serially connected to said plurality of resistances at said second end point; said drive means magnet being in magnetic communication with at least one of said magnetically actuated switches; and means for measuring the voltage generated between said second current source and said common node to obtain a second voltage.
Claim 5
Dependent Claim
25 words
The coupling indicator system according to claim 3 wherein said position indicator magnet is located intermediate the drive means magnet and said first end point.
Claim 6
Dependent Claim
21 words
The coupling indicator system according to claim 3 wherein said first electrical polarity and said second electrical polarity are electrically opposite.
Claim 7
Dependent Claim
44 words
The coupling indicator system according to claim 3 wherein said means for comparing the axial position of said plunger with respect to the axial position of said drive means comprises means for measuring the voltage differential between said first voltage and said second voltage.
Claim 8
Dependent Claim
80 words
The coupling indicator system according to claim 6 wherein said means for measuring the voltage differential comprise: a voltage dependent first comparator, said first comparator being electrically conducting at voltages greater than a first predetermined input voltage and electrically non-conducting at voltages less than said first predetermined voltage input; and first means for indicating the electrical conduction of said first comparator, said voltage differential between said first voltage and said second voltage being a voltage input to said first comparator.
Claim 9
Dependent Claim
122 words
The coupling indicator system according to claim 7 wherein the voltage differential between said first voltage and said second voltage when said control rod is coupled to said drive shaft is greater than the voltage differential between said first voltage and said second voltage when said control rod is uncoupled from said drive shaft; and said first predetermined input voltage is less than the voltage differential between said first voltage and said second voltage when said control rod is coupled to said drive shaft and is greater than the voltage differential between said first voltage and said second voltage when said control rod is uncoupled from said drive shaft, whereby said first comparator is electrically conducting when said control rod is coupled.
Claim 10
Dependent Claim
80 words
The coupling indicator system according to claim 6 wherein said means for measuring the voltage differential comprise: a voltage dependent second comparator, said second comparator being electrically non-conducting at voltages greater than a second predetermined input voltage and electrically conducting at voltages less than said second predetermined input voltage; and second means for indicating the electrical conduction of said second comparator, said voltage differential between said first voltage and said second voltage being a voltage input to said second comparator.
Claim 11
Dependent Claim
126 words
The coupling indicator system according to claim 9 wherein the voltage differential between said first voltage and said second voltage when said control rod is coupled to said drive shaft is greater than the voltage differential between said first voltage and said second voltage when said control rod is uncoupled from said drive shaft; and said second predetermined input voltage is greater than the voltage differential between said first voltage and said second voltage when said control rod is uncoupled from said drive shaft, and is less than the voltage differential between said first voltage and said second voltage when said control rod is coupled to said drive shaft, whereby said second comparator is electrically conducting when said control rod is uncoupled to said drive shaft.
References Cited (Backward Citations)
US3296081A
Cited
GB965014A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |