US4115731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for locating electrical shorts by tracking the paths of injected pulse currents utilizing a voltage differential responsive probe
Assignee: DIGITAL FACILITIES Inc
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Filing: 1976-06-01
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Granted: 1978-09-19
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Expires: 1996-06-01
Abstract
Abstract Disclosed is a system for locating electrical shorts between a pair of conductors. A current is tracked along the conductors and/or their branch conductors until the current path disappears at a location where there is no intentional conductor branching.
Inventors
- 👤 Clyde R. Axtell, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:24
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/08; G01R31/088; G01R31/50; G01R31/52
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
135 words
A system for locating an electrical short between PCB conductors, said system comprising: pulse generating means for injecting a low amplitude pulse train into the circuit path formed by said conductors and said short, first and second probe means suitable for contacting exclusively even a narrow width conductor closely adjacent another conductor, probe holding means for receiving said first and second probe means and maintaining a substantially constant small separation therebetween, indicator means having at least first and second indicating states, and means responsive to voltage differential between said first and second probe means for effecting a change in said indicator means from said first indicating state to said second indicating state only after the voltage differential between said probe means manifests reception by said probe means of at least two pulses of predetermined amplitude.
Claim 2
Independent Claim
135 words
A system for locating an electrical short between PCB conductors, said system comprising: pulse generating means for injecting a low amplitude pulse train into the circuit path formed by said conductors and said short, first and second probe means suitable for contacting exclusively even a narrow width conductor closely adjacent another conductor, probe holding means for receiving said first and second probe means and maintaining a substantially constant small separation therebetween, indicator means having at least first and second indicating states, and means responsive to voltage differential between said first and second probe means for effecting a change in said indicator means from said first indicating state to said second indicating state only after the voltage differential between said probe means manifests reception by said probe means of at least two pulses of predetermined amplitude.
Claim 3
Dependent Claim
48 words
A system as defined in claim 1 wherein said means responsive to voltage differential comprises means for effecting said indicator means change from said first indicating state to said second indicating state only after there is manifested reception of at least two successive pulses of said pulse train.
Claim 4
Dependent Claim
18 words
A system as defined in claim 2 wherein said pulse train is a low duty cycle pulse train.
Claim 5
Dependent Claim
27 words
A system as defined in claim 3 including means for effecting a third indicating state when said circuit path is not connected to said pulse generating means.
Claim 6
Dependent Claim
33 words
A system as defined in claim 4 wherein said means responsive to voltage differential for effecting a change in indicator means state is responsive to said means for effecting a third indicating state.
Claim 7
Dependent Claim
51 words
A system as defined in claim 5 wherein said means responsive to voltage differential for effecting a change in indicator means state includes absolute value circuit means for making the operation of said voltage differential responsive means independent of the polarity of one probe means relative to the other probe means.
Claim 8
Independent Claim
141 words
A system for locating an electrical short between PCB conductors, said system comprising: pulse generating means for injecting a low amplitude pulse train of low duty cycle into the circuit path formed by said conductors and said short, first and second probe means suitable for contacting exclusively even a narrow width conductor closely adjacent another conductor, probe holding means for receiving said first and second probe means and maintaining a substantially constant small separation therebetween, indicator means having at least first and second indicating states, and means responsive to voltage differential between said first and second probe means for effecting a change in said indicator means from said first indicating state to said second indicating state only after the voltage differential between said probe means manifests reception by said probe means of a predetermined plural number of pulses of predetermined amplitude.
Claim 9
Independent Claim
141 words
A system for locating an electrical short between PCB conductors, said system comprising: pulse generating means for injecting a low amplitude pulse train of low duty cycle into the circuit path formed by said conductors and said short, first and second probe means suitable for contacting exclusively even a narrow width conductor closely adjacent another conductor, probe holding means for receiving said first and second probe means and maintaining a substantially constant small separation therebetween, indicator means having at least first and second indicating states, and means responsive to voltage differential between said first and second probe means for effecting a change in said indicator means from said first indicating state to said second indicating state only after the voltage differential between said probe means manifests reception by said probe means of a predetermined plural number of pulses of predetermined amplitude.
Claim 10
Dependent Claim
18 words
A system as defined in claim 7 wherein said predetermined number of pulses comprises at least two pulses.
Claim 11
Dependent Claim
20 words
A system as defined in claim 8 wherein the amplitude of said pulse train does not exceed approximately four volts.
Claim 12
Dependent Claim
17 words
A system as defined in claim 9 wherein said separation between probe means is approximately 0.3 inches.
Claim 13
Dependent Claim
21 words
A system as defined in claim 10 wherein said duty cycle is in the range of approximately 0.03% to approximately 0.3%.
Claim 14
Independent Claim
156 words
A system for locating an electrical short between PCB conductors, said system comprising: pulse generating means for injecting a pulse train into the circuit path formed by said conductors and said short, first and second probe means suitable for contacting exclusively even a narrow width conductor closely adjacent another conductor, probe holding means for receiving said first and second probe means and maintaining a substantially constant small separation therebetween, indicator means having at least first, second, and third indicating states, and means responsive to voltage differential between said first and second probe means for effecting a change in said indicator means from said first indicating state to said second indicating state only after the voltage differential between said probe means manifests reception by said probe means of a predetermined plural number of pulses of predetermined amplitude, and means for effecting said third indicating state when said circuit path is not connected to said pulse generating means.
Claim 15
Independent Claim
156 words
A system for locating an electrical short between PCB conductors, said system comprising: pulse generating means for injecting a pulse train into the circuit path formed by said conductors and said short, first and second probe means suitable for contacting exclusively even a narrow width conductor closely adjacent another conductor, probe holding means for receiving said first and second probe means and maintaining a substantially constant small separation therebetween, indicator means having at least first, second, and third indicating states, and means responsive to voltage differential between said first and second probe means for effecting a change in said indicator means from said first indicating state to said second indicating state only after the voltage differential between said probe means manifests reception by said probe means of a predetermined plural number of pulses of predetermined amplitude, and means for effecting said third indicating state when said circuit path is not connected to said pulse generating means.
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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) | 1981-09-18 | 1982-03-20 | 1982-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-18 | 1986-03-20 | 1986-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-18 | 1990-03-20 | 1990-09-19 | $7700.00 | Window Closed / Lapsed |