US3841810A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for detection of shield imperfections in electrical conductors
Assignee: General Cable Corp
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Filing: 1972-09-25
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Granted: 1974-10-15
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Expires: 1992-09-25
Abstract
Abstract This invention uses a tip, or tip assembly, of an extrusion die as an electrode for detecting skips or other imperfections in the strand shield on the conductor of an electrical cable. The tip is insulated from the extruder, or otherwise insulated from ground, so that some electrical potential can be maintained on the tip. Changes between the tip potential and that of the extruder or ground are used to detect defects in the strand shield on the cable. Defects in the strand shield are detected and the location recorded by the detector, and can be detected and recorded on a tape or other record so that the location of the defect along the length of the cable is known.
Inventors
- 👤 D Robinson
- 👤 R Schmidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:47
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/32; B29C48/34; B29C48/03; B29C48/06; B29C48/92; B29C2948/00; B29C2948/92; B29C2948/92009; B29C2948/92238; B29C2948/92295; B29C2948/92304; B29C2948/92323; B29C2948/92352; B29C2948/92361; B29C2948/92409; B29C2948/92447; B29C48/05
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
128 words
Apparatus for detecting imperfections in strand shields on electrical cable conductors including in combination an extruder that extrudes a layer of insulation over the strand shield, the extruder comprising a die and a tip within the die and forming with the die an outlet orifice through which the insulation is extruded, the tip having an axial passage through which the strand shielded conductor passes with continuous motion, means for maintaining an electrical potential between the tip and the conductor, and means for detecting changes in current produced by said potential, from a normal current, as a result of variations in resistance between the tip and conductor, an interior surface of the axial passage of the tip being adjacent to the surface of the strand shield on the conductor.
Claim 2
Dependent Claim
128 words
Apparatus for detecting imperfections in strand shields on electrical cable conductors including in combination an extruder that extrudes a layer of insulation over the strand shield, the extruder comprising a die and a tip within the die and forming with the die an outlet orifice through which the insulation is extruded, the tip having an axial passage through which the strand shielded conductor passes with continuous motion, means for maintaining an electrical potential between the tip and the conductor, and means for detecting changes in current produced by said potential, from a normal current, as a result of variations in resistance between the tip and conductor, an interior surface of the axial passage of the tip being adjacent to the surface of the strand shield on the conductor.
Claim 3
Dependent Claim
23 words
The apparatus described in claim 1 characterized by said inside surface of the tip being electrically insulated from the rest of the extruder.
Claim 4
Dependent Claim
30 words
The apparatus described in claim 1 characterized by the tip and parts of the apparatus that hold the tip in place being electrically insulated from the rest of the extruder.
Claim 5
Dependent Claim
37 words
The apparatus described in claim 1 characterized by the tip having two longitudinally spaced surfaces that are adjacent to the shielded conductor and that are insulated from one another and between which an electrical potential is maintained.
Claim 6
Dependent Claim
34 words
The apparatus described in claim 4 characterized by the two surfaces of the tip that are electrically insulated from one another being in position to contact with imperfections in the shielding on the conductor.
Claim 7
Dependent Claim
60 words
The apparatus described in claim 1 characterized by the tip having an inside diameter along most of its length that is larger than the outside diameter of the shielded cable, and the downstream end of the tip having a reduced inside diameter substantially equal to the outside diameter of the shielded conductor where the shielded conductor is free of imperfections.
Claim 8
Dependent Claim
36 words
The apparatus described in claim 6 characterized by the tip having two longitudinally spaced surfaces that are electrically insulated from one another, both of which surfaces are located along the reduced inside diameter of the tip.
Claim 9
Dependent Claim
61 words
The apparatus described in claim 1 characterized by mechanism that passes a shielded conductor through the tip with continuous longitudinal motion, a recorder that operates at a speed proportional to the speed of longitudinal movement of the shielded conductor, and means responsive to the detector for indicating on the record the location of imperfections along the length of the shielded conductor.
Claim 10
Dependent Claim
63 words
The apparatus described in claim 8 characterized by the recorder including a record that moves at a rate proportional to the travel of the cable, a scriber that traces a line on the record, an electromagnetic means responsive to the detector for moving the scriber to form spikes in the line whenever an imperfection in the shielding instigates a response from the detector.
Claim 11
Dependent Claim
81 words
The apparatus described in claim 9 characterized by the record being a tape that winds on a reel, the tip being part of an extruder that applies a jacket of insulation over the shielding on the conductor, means for wrapping the insulated cable on a spool, and coordinated motor means that wind the cable and the tape at longitudinal speeds proportional to one another whereby the record indicAtes the location along the length of the cable where any imperfection was detected.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |