US5097247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat actuated fuse apparatus with solder link
Assignee: MMC BIDDING Inc
•
Filing: 1991-06-03
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Granted: 1992-03-17
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Expires: 2011-06-03
Abstract
Abstract An apparatus for protecting circuitry includes a heat actuated fuse which opens at a predetermined temperature and a resistive device disposed proximate the fuse for heating the fuse in response to an electrical current passed through the device. The fuse includes first and second electrodes bridged by a solder link which melts at the predetermined temperature and retreats to the electrodes. A quantity of flux-containing material is disposed on the link to promote rapid and complete retreat of the solder when the fuse is actuated.
Inventors
- 👤 Bernhard E. Doerrwaechter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:16
CPC Classifications
H; H01; H01H; H01H85/00; H01H85/02; H01H85/04; H01H85/041; H01H85/046; H05; H05K; H05K1/00; H05K1/02; H05K1/0286; H05K1/0293; H01H85/0039; H01H85/0047; H01H85/0052; H05K2201/00; H05K2201/03; H05K2201/0302; H05K2201/0305; H05K2201/10; H05K2201/10007; H05K2201/10181; H05K3/00; H05K3/22; H05K3/28; H05K3/30; H05K3/32; H05K3/34; H05K3/3489; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49107
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
203 words
A heat actuated fuse for opening at a predetermined actuation temperature, said fuse comprising: a. an electrically insulating substrate; b. first and second electrodes disposed on a surface of the substrate in a spaced apart relationship to define a gap therebetween, each of said electrodes comprising a layer of electrically conductive material; c. a layer of a first solder material disposed on each of the first and second electrodes, said first solder material having a melting temperature which is substantially higher than the predetermined actuation temperature; d. a conductive link extending across the gap and disposed on at least a portion of each of said first and second electrodes and on the surface of the substrate between said electrodes, said conductive link comprising a predetermined quantity of a second solder material which is in contact with the layer of solder on each of the first and second electrodes, said second solder material having a melting temperature which substantially corresponds to the predetermined actuation temperature, and said predetermined quantity of said second solder material being containable on the first and second electrodes after melting; and e. a quantity of flux containing material disposed in contact with at least a portion of the conductive link.
Claim 2
Dependent Claim
203 words
A heat actuated fuse for opening at a predetermined actuation temperature, said fuse comprising: a. an electrically insulating substrate; b. first and second electrodes disposed on a surface of the substrate in a spaced apart relationship to define a gap therebetween, each of said electrodes comprising a layer of electrically conductive material; c. a layer of a first solder material disposed on each of the first and second electrodes, said first solder material having a melting temperature which is substantially higher than the predetermined actuation temperature; d. a conductive link extending across the gap and disposed on at least a portion of each of said first and second electrodes and on the surface of the substrate between said electrodes, said conductive link comprising a predetermined quantity of a second solder material which is in contact with the layer of solder on each of the first and second electrodes, said second solder material having a melting temperature which substantially corresponds to the predetermined actuation temperature, and said predetermined quantity of said second solder material being containable on the first and second electrodes after melting; and e. a quantity of flux containing material disposed in contact with at least a portion of the conductive link.
Claim 3
Dependent Claim
18 words
A fuse as in claim 1 including a protective covering extending over at least the flux containing material.
Claim 4
Dependent Claim
24 words
A fuse as in claim 2 where the protective covering extends over the layer of flux containing material and the first and second electrodes.
Claim 5
Dependent Claim
19 words
A fuse as in claim 1 or 2 where the flux containing material consists essentially of a flux paste.
Claim 6
Dependent Claim
19 words
A fuse as in claim 1 or 2 where the flux containing material comprises a solder material containing flux.
Claim 7
Dependent Claim
15 words
A fuse as in claim 5 where the flux containing material comprises a solder paste.
Claim 8
Dependent Claim
23 words
A fuse as in claim 1 or 2 where the flux containing material extends across substantially the entire length of the conductive link.
Claim 9
Dependent Claim
15 words
A fuse as in claim 1 or 2 where the substrate comprises a ceramic material.
Claim 10
Dependent Claim
14 words
A fuse as in claim 8 where the ceramic material consists essentially of alumina.
Claim 11
Dependent Claim
15 words
A fuse as in claim 1 or 2 where the substrate comprises a phenolic material.
Claim 12
Dependent Claim
31 words
A fuse as in claim 1 or 2 where said portion of each of the first and second electrodes comprises a tab portion of the electrode projecting toward the other electrode.
Claim 13
Dependent Claim
29 words
A fuse as in claim 1 or 2 where said portion of each of the first and second electrodes comprises an inwardly extending portion of each of said electrodes.
Claim 14
Independent Claim
254 words
An apparatus for protecting circuitry including at least one circuit element, said apparatus comprising a heat actuated fuse, which opens at a predetermined temperature, for carrying electrical current to the protected circuitry, a resistive device disposed for effecting heating of said fuse in response to an electrical current passed through said device, and means for applying said current to said resistive device, said fuse comprising: a. an electrically insulating substrate; b. first and second electrodes disposed on a surface of the substrate in a spaced apart relationship to define a gap therebetween, each of said electrodes comprising a layer of electrically conductive material; c. a layer of a first solder material disposed on each of the first and second electrodes, said first solder material having a melting temperature which is substantially higher than the predetermined actuation temperature; d. a conductive link extending across the gap and disposed on at least a portion of each of said first and second electrodes and on the surface of the substrate between said electrodes, said conductive link comprising a predetermined quantity of a second solder material which is in contact with the layer of solder on each of the first and second electrodes, said second solder material having a melting temperature which substantially corresponds to the predetermined actuation temperature, and said predetermined quantity of said second solder material being containable on the first and second electrodes after melting; and e. a quantity of flux containing material disposed in contact with at least a portion of the conductive link.
Claim 15
Independent Claim
254 words
An apparatus for protecting circuitry including at least one circuit element, said apparatus comprising a heat actuated fuse, which opens at a predetermined temperature, for carrying electrical current to the protected circuitry, a resistive device disposed for effecting heating of said fuse in response to an electrical current passed through said device, and means for applying said current to said resistive device, said fuse comprising: a. an electrically insulating substrate; b. first and second electrodes disposed on a surface of the substrate in a spaced apart relationship to define a gap therebetween, each of said electrodes comprising a layer of electrically conductive material; c. a layer of a first solder material disposed on each of the first and second electrodes, said first solder material having a melting temperature which is substantially higher than the predetermined actuation temperature; d. a conductive link extending across the gap and disposed on at least a portion of each of said first and second electrodes and on the surface of the substrate between said electrodes, said conductive link comprising a predetermined quantity of a second solder material which is in contact with the layer of solder on each of the first and second electrodes, said second solder material having a melting temperature which substantially corresponds to the predetermined actuation temperature, and said predetermined quantity of said second solder material being containable on the first and second electrodes after melting; and e. a quantity of flux containing material disposed in contact with at least a portion of the conductive link.
Claim 16
Dependent Claim
18 words
An apparatus as in claim 13 including a protective covering extending over at least the flux containing material.
Claim 17
Dependent Claim
21 words
An apparatus as in claim 13 or 14 where the fuse and the resistive device are disposed on the same substrate.
Claim 18
Dependent Claim
45 words
An apparatus as in claim 15 where the means for applying the current to the resistive device includes a first terminal electrically connected to a first part of the resistive device and a second terminal electrically connected to a second part of the resistive device.
Claim 19
Dependent Claim
34 words
An apparatus as in claim 16 where the first terminal is electrically connected to the first electrode of the fuse and including a third terminal electrically connected to the second electrode of the fuse.
Claim 20
Dependent Claim
29 words
An apparatus as in claim 15 where the protected circuitry is disposed on the substrate and is electrically connected to the fuse by conductive means disposed on the substrate.
Claim 21
Dependent Claim
15 words
An apparatus as in claim 15 where the resistive device is disposed proximate the fuse.
Claim 22
Dependent Claim
17 words
An apparatus as in claim 13 or 14 where the resistive device comprises a thick film resistor.
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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) | 1995-03-17 | 1995-09-16 | 1996-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-17 | 1999-09-16 | 2000-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-17 | 2003-09-16 | 2004-03-17 | $7700.00 | Window Closed / Lapsed |