Patent US3936730A successfully refreshed from Google Patents.
US3936730A
Expired / Lapsed
US
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Insulation test apparatus including improved means for simultaneous display
Assignee: Westinghouse Electric Corp
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Filing: 1971-05-24
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Granted: 1976-02-03
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Expires: 1991-05-24
Abstract
Abstract In apparatus for the high frequency voltage testing of insulation on conductors, a display technique is disclosed in which a plurality of insulated conductors under test are in mutually parallel circuit branches all connected in a single capacitor discharge circuit and associated with means for simultaneously displaying signals indicative of current variations in each of the parallel circuit branches. This technique of simultaneous display not only minimizes the components in the circuit but more importantly provides a more sensitive and faster responding test apparatus.
Inventors
- 👤 Paul F. Pittman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:17
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/12; G01R31/1227; G01R31/1263; G01R31/1272
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
89 words
In insulation test apparatus wherein a capacitor discharge applies a high frequency voltage to an insulated conductor under test and producing a waveform whose characteristics, including frequency, indicate the quality of insulation on the conductor, the improvement comprising: means to connect a plurality of insulated conductors under test respectively in mutually parallel circuit branches which are all connected in a single capacitor discharge circuit; means for sensing current variations in each of said parallel circuit branches; means for displaying signals from each of said means for sensing current variations.
Claim 2
Dependent Claim
89 words
In insulation test apparatus wherein a capacitor discharge applies a high frequency voltage to an insulated conductor under test and producing a waveform whose characteristics, including frequency, indicate the quality of insulation on the conductor, the improvement comprising: means to connect a plurality of insulated conductors under test respectively in mutually parallel circuit branches which are all connected in a single capacitor discharge circuit; means for sensing current variations in each of said parallel circuit branches; means for displaying signals from each of said means for sensing current variations.
Claim 3
Dependent Claim
54 words
The subject matter of claim 1 wherein: said single capacitor discharge circuit comprises a capacitor that is also connected in a charging circuit to charge it to a desired voltage level, switching means to close said discharge circuit, and two of said mutually parallel circuit branches, each for a separate insulated conductor under test.
Claim 4
Dependent Claim
33 words
The subject matter of claim 2 wherein: said means for sensing current variations in each of sapid parallel circuit branches is a current transformer and said means for displaying signals is an oscilloscope.
Claim 5
Dependent Claim
44 words
The subject matter of claim 2 wherein: said switching means comprises a plurality of semiconductor switching devices of the four layer type connected in a series string and provided with means to trigger said series string to conduction to effect discharge of said capacitor.
Claim 6
Dependent Claim
35 words
The subject matter of claim 1 wherein: said means for displaying signals has alternately applied thereto signals from each of said means for sensing current variations at a rate to produce an apparent simultaneous display.
Claim 7
Dependent Claim
32 words
The subject matter of claim 1 wherein: said means for displaying signals has means to develop a signal representing the difference of two parallel circuit branches and to display that difference signal.
Claim 8
Dependent Claim
24 words
The subject matter of claim 6 wherein: said apparatus further comprises indicia means to indicate the existence of a given magnitude of difference signal.
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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) | 1979-02-02 | 1979-08-04 | 1980-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-02 | 1983-08-04 | 1984-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-02 | 1987-08-04 | 1988-02-03 | $7700.00 | Window Closed / Lapsed |