US3978443A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fusible resistor
Assignee: ERIE ELECTRONICS Ltd
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Filing: 1974-10-04
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Granted: 1976-08-31
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Expires: 1994-10-04
Abstract
Abstract A fusible resistor has a substrate on which two terminal paths are formed. A resistor in the form of an area of resistive material deposited onto the substrate extends between the terminal paths. The expected line of fracture of the substrate, upon a current flowing through the resistor such that the rate wattage is exceeded, crosses at least one of the terminal paths. Desirably at least one line or zone of weakness is formed in the substrate.
Inventors
- 👤 Colin Dennis
- 👤 Arthur Denys Holt
- 👤 Patrick William Henry Moore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:35
CPC Classifications
H; H01; H01H; H01H85/00; H01H85/02; H01H85/04; H01H85/041; H01H85/046; H01H85/0241; H01H2085/0275; H01H85/0039; H01H85/0073
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
163 words
A fuse comprising a substrate, two terminal paths of conductive material formed on said substrate, and a resistor carried by said substrate and extending between said terminal paths, said resistor constructed to form a line of maximum thermal stress in said substrate upon a current passing through said resistor which line of maximum thermal stress in turn defines an expected line of fracture of said substrate such that the substrate fractures nearly along said expected line of fracture when the rated wattage for the fuse is exceeded, wherein at least one of said terminal paths includes a first portion adjacent and contacting said resistor and a second portion spaced from said first portion so that an area of the substrate separates said first and second portions of said terminal path, and wherein said expected line of fracture respectively crosses said first portion of said last mentioned terminal path, said area of said substrate and said second portion of said last mentioned terminal path.
Claim 2
Dependent Claim
163 words
A fuse comprising a substrate, two terminal paths of conductive material formed on said substrate, and a resistor carried by said substrate and extending between said terminal paths, said resistor constructed to form a line of maximum thermal stress in said substrate upon a current passing through said resistor which line of maximum thermal stress in turn defines an expected line of fracture of said substrate such that the substrate fractures nearly along said expected line of fracture when the rated wattage for the fuse is exceeded, wherein at least one of said terminal paths includes a first portion adjacent and contacting said resistor and a second portion spaced from said first portion so that an area of the substrate separates said first and second portions of said terminal path, and wherein said expected line of fracture respectively crosses said first portion of said last mentioned terminal path, said area of said substrate and said second portion of said last mentioned terminal path.
Claim 3
Dependent Claim
34 words
The fuse as defined in claim 1 wherein the resistor carried by the substrate is in the form of an area of resistive material deposited onto the substrate and extending between the terminal paths.
Claim 4
Dependent Claim
18 words
The fuse as defined in claim 1 which is formed with a zone of weakness in the substrate.
Claim 5
Dependent Claim
17 words
The fuse as defined in claim 3 wherein the zone of weakness is provided by a groove.
Claim 6
Dependent Claim
54 words
The fuse as defined in claim 4 wherein the resistor carried by the substrate is in the form of an area of resistive material deposited onto the substrate and extending between the terminal paths and wherein the groove is on the side of the substrate on which the area of resistive material is deposited.
Claim 7
Dependent Claim
57 words
The fuse as defined in claim 4 wherein the resistor carried by the substrate is in the form of an area of resistive material deposited onto the substrate and extending between the terminal paths and wherein the groove is on the opposite side of the substrate to that on which the area of resistive material is deposited.
Claim 8
Dependent Claim
30 words
The fuse as defined in claim 3 wherein the zone of weakness is formed by a notch in at least one edge of the substrate to which the zone extends.
Claim 9
Dependent Claim
26 words
The fuse as defined in claim 3 wherein the expected path of fracture passes at least partially along through the zone of weakness in the substrate.
Claim 10
Dependent Claim
95 words
The fuse as defined in claim 2 wherein the substrate is generally rectangular and wherein termination tags are secured to corresponding ends of the long edges of the substrate, the area of resistive material being formed adjacent to the other end of the substrate, the terminal paths being parallel to the long edges of the substrate, the end of each terminal path near to the said other end of the substrate being extended to the corresponding termination tag and so as to be spaced from it portion to which the area of resistive material extends.
Claim 11
Dependent Claim
106 words
A fuse as defined in claim 2 wherein the substrate is generally rectangular and wherein termination tags are secured to the substrate at its opposed short edges and wherein the first and second portions of at least one of said terminal paths are parallel to the long edges of the substrate, said second portion of said last mentioned terminal path extending from one of the termination tags along one long edge of said substrate, wherein said last mentioned terminal path includes a portion connecting the ends of the first and second portions of said last mentioned terminal path most remote from said last mentioned termination tag.
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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) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |