Patent US3896343A successfully refreshed from Google Patents.
US3896343A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat-operated short-circuiting arrangements
Assignee: DUBILIER INTERNATIONAL PLC DUBILIER HOUSE RADLEY RD ABINGDON OXFORDSHIRE OX14 3XA ENGLAND A BRITISH Co
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Filing: 1974-03-21
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Granted: 1975-07-22
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Expires: 1994-03-21
Abstract
Abstract A heat-operated short-circuiting arrangement comprising an enclosure formed at least partly of a heat-shrinkable material; a pair of terminals for external connection of the arrangement which provide spaced surfaces within the enclosure; and at least one element of a fusible, electrically conductive material housed within the enclosure; the arrangement being such that the fusible element or elements melt on heating of the arrangement and the resultant molten material is caused to flow due to shrinking of the heat shrinkable material to a position where the molten material establishes electrical connection between said spaced surfaces of the terminals. The arrangement finds application in combination with an electrical device for short-circuiting a pair of terminals of the device in the event of overheating of the device.
Inventors
- 👤 Basil Offor Baker
- 👤 John William Ellis Ross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:44
CPC Classifications
H; H01; H01T; H01T1/00; H01T1/14; H01H; H01H37/00; H01H37/74; H01H37/76; H01H37/767; H01R; H01R4/00; H01R4/70; H01R4/72; H01R4/723; H01H2037/768
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
95 words
A heat-operated short circuiting arrangement comprising: an enclosure formed at least partly of a heat-shrinkable material; a pair of terminals for external connection of the arrangement which provide spaced surfaces within the enclosure; at least one element of a fusible, electrically conductive material housed within the enclosure; and means providing a space within said enclosure between said spaced surfaces through which, on heating of the arrangement, molten material, produced by melting of said fusible material is caused to flow due to shrinking of said heat shrinkable material to establish electrical connection between said spaced surfaces.
Claim 2
Dependent Claim
95 words
A heat-operated short circuiting arrangement comprising: an enclosure formed at least partly of a heat-shrinkable material; a pair of terminals for external connection of the arrangement which provide spaced surfaces within the enclosure; at least one element of a fusible, electrically conductive material housed within the enclosure; and means providing a space within said enclosure between said spaced surfaces through which, on heating of the arrangement, molten material, produced by melting of said fusible material is caused to flow due to shrinking of said heat shrinkable material to establish electrical connection between said spaced surfaces.
Claim 3
Dependent Claim
17 words
An arrangement according to claim 1 wherein said fusible material is an alloy of tin and lead.
Claim 4
Dependent Claim
68 words
An arrangement according to claim 1 in combination with an electrical device having a pair of terminals; electrical connections between said pair of terminals of the device and said pair of terminals of the short circuiting arrangement; and a thermal connection between said enclosure and said electrical device so that said pair of terminals of the device are short circuited in the event of overheating of the device.
Claim 5
Dependent Claim
14 words
An arrangement according to claim 3 wherein said device is an excess voltage arrester.
Claim 6
Dependent Claim
15 words
An arrangement according to claim 3 wherein said enclosure is formed partly by said device.
Claim 7
Dependent Claim
47 words
An arrangement according to claim 5 wherein the device is of generally cylindrical form, said pair of terminals of the device provide annular surfaces spaced axially along the device, and said enclosure is of annular form and encloses at least part of each of said annular surfaces.
Claim 8
Dependent Claim
41 words
An arrangement according to claim 6 including two said fusible elements which before melting are of annular form and are located by means of a spacer of electrically insulating material in positions respectively surrounding said enclosed parts of said annular surfaces.
Claim 9
Dependent Claim
41 words
An arrangement according to claim 7 wherein said spacer fits loosely around the device to provide, between the spacer and the device, said space through which the molten material is caused to flow to establish electrical connection between said spaced surfaces.
Claim 10
Dependent Claim
22 words
An arrangement according to claim 8 wherein the ends of the spacer locate on shoulders provided on said fusible elements before melting.
Claim 11
Dependent Claim
21 words
An arrangement according to claim 6 wherein said heat-shrinkable material is in the form of a sleeve coaxially surrounding the device.
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) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |