US5446774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spud finger gauge
Assignee: General Electric Co
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Filing: 1994-02-15
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Granted: 1995-08-29
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Expires: 2014-02-15
Abstract
Abstract A tool for checking the required spacing between adjacent fingers of the spud in a control rod drive. The tool is a GO-NO-GO gauge with tight tolerance. The spud finger gauge has two circular cylindrical pins of different diameter. One pin (i.e., the GO pin) has a diameter less than the required spacing between adjacent fingers of the spud. The other pin (i.e., the NO GO pin) has a diameter greater than the required spacing between adjacent fingers of the spud. The spacing is correct if the GO pin passes through the spacing and the NO GO pin does not.
Inventors
- 👤 Harry I. Russell
- 👤 Bettadapur N. Sridhar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:33
CPC Classifications
G; G21; G21C; G21C17/00; G21C7/00; G21C7/06; G21C7/08; G21C7/12; G21C7/16; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
130 words
A spud finger gauge comprising a handle having first and second ends, a first cylindrical projection integrally connected to said first end of said handle and having a transverse dimension of first magnitude and a second cylindrical projection integrally connected to said second end of said handle and having a transverse dimension of second magnitude, said first and second magnitudes being selected such that said first and second cylindrical projections respectively pass and do not pass through a spud finger spacing having a width of third magnitude, said third magnitude being within a predetermined range of magnitudes defined by a minimum acceptable magnitude and a maximum acceptable magnitude, wherein said first magnitude is less than said minimum acceptable magnitude and said second magnitude is greater than said maximum acceptable magnitude.
Claim 2
Dependent Claim
130 words
A spud finger gauge comprising a handle having first and second ends, a first cylindrical projection integrally connected to said first end of said handle and having a transverse dimension of first magnitude and a second cylindrical projection integrally connected to said second end of said handle and having a transverse dimension of second magnitude, said first and second magnitudes being selected such that said first and second cylindrical projections respectively pass and do not pass through a spud finger spacing having a width of third magnitude, said third magnitude being within a predetermined range of magnitudes defined by a minimum acceptable magnitude and a maximum acceptable magnitude, wherein said first magnitude is less than said minimum acceptable magnitude and said second magnitude is greater than said maximum acceptable magnitude.
Claim 3
Dependent Claim
50 words
The spud finger gauge as defined in claim 1, wherein said first cylindrical projection has a circular cross section of first diameter and said second cylindrical projection has a circular cross section of second diameter, said first magnitude being said first diameter and said second magnitude being said second diameter.
Claim 4
Dependent Claim
37 words
The spud finger gauge as defined in claim 2, wherein said handle is a circular cylinder having an axis, said first and second cylindrical projections being disposed at opposite ends of said handle coaxial with said axis.
Claim 5
Dependent Claim
16 words
The spud finger gauge as defined in claim 3, wherein said handle has a knurled surface.
Claim 6
Dependent Claim
26 words
The spud finger gauge as defined in claim 1, wherein said handle and said first and second cylindrical projections are made of corrosion-resistant hardened stainless steel.
Claim 7
Independent Claim
178 words
A method for checking the condition of a spud in a control rod drive, said spud having a plurality of fingers and a plurality of spacings, said fingers being arranged along a circumference with a corresponding one of said plurality of spacings separating each pair of adjacent fingers, comprising the steps of: (a) trying to pass a first cylindrical projection having a transverse dimension of first magnitude through a first spacing of said plurality of spacings; and (b) trying to pass a second cylindrical projection having a transverse dimension of second magnitude through said first spacing, wherein said first and second magnitudes are selected such that said first and second cylindrical projections respectively pass and do not pass through any spacing separating adjacent fingers of an undeformed spud having a spacing width of third magnitude, said third magnitude being within a predetermined range of magnitudes defined by a minimum acceptable magnitude and a maximum acceptable magnitude, wherein said first magnitude is less than said minimum acceptable magnitude and said second magnitude is greater than said maximum acceptable magnitude.
Claim 8
Independent Claim
178 words
A method for checking the condition of a spud in a control rod drive, said spud having a plurality of fingers and a plurality of spacings, said fingers being arranged along a circumference with a corresponding one of said plurality of spacings separating each pair of adjacent fingers, comprising the steps of: (a) trying to pass a first cylindrical projection having a transverse dimension of first magnitude through a first spacing of said plurality of spacings; and (b) trying to pass a second cylindrical projection having a transverse dimension of second magnitude through said first spacing, wherein said first and second magnitudes are selected such that said first and second cylindrical projections respectively pass and do not pass through any spacing separating adjacent fingers of an undeformed spud having a spacing width of third magnitude, said third magnitude being within a predetermined range of magnitudes defined by a minimum acceptable magnitude and a maximum acceptable magnitude, wherein said first magnitude is less than said minimum acceptable magnitude and said second magnitude is greater than said maximum acceptable magnitude.
Claim 9
Dependent Claim
24 words
The method as defined in claim 6, wherein said steps (a) and (b) are repeated for every other one of said plurality of spacings.
Claim 10
Dependent Claim
48 words
The method as defined in claim 6, wherein said first cylindrical projection has a circular cross section of first diameter and said second cylindrical projection has a circular cross section of second diameter, said first magnitude being said first diameter and said second magnitude being said second diameter.
Claim 11
Dependent Claim
24 words
The method as defined in claim 6, wherein said predetermined range of magnitudes corresponds to the tolerances for spacing width in an undeformed spud.
References Cited (Backward Citations)
US3785059A
Cited
US4058901A
Cited
US4094369A
Cited
US4092213A
Cited
US4543638A
Cited
US4696190A
Cited
US4790079A
Cited
US4790073A
Cited
US4868992A
Cited
US4863673A
Cited
US5315259A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-28 | 1999-02-27 | 1999-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-28 | 2003-02-27 | 2003-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-28 | 2007-02-27 | 2007-08-29 | $7700.00 | Window Closed / Lapsed |