Patent US3936621A successfully refreshed from Google Patents.
US3936621A
Expired / Lapsed
US
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Destructible type switch having frangible conductive element
Assignee: Imperial Chemical Industries Ltd
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Filing: 1974-10-15
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Granted: 1976-02-03
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Expires: 1994-10-15
Abstract
Abstract A detector comprises a brittle support for an electrical conductor adapted to fit adjacent a closure (e.g. a bursting disc) so that when failure occurs, electrical continuity in the conductor is broken by fracture of the support and cannot be fortuitously remade.
Inventors
- 👤 Alfred Palin
- 👤 John Wesley Slack
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:19
CPC Classifications
E; E05; E05B; E05B17/00; B; B01; B01J; B01J19/00; B01J19/0053; B01J19/0073; H; H01; H01H; H01H3/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
149 words
A detector for the detection of a rupture of a closure member, operable by the breakage of an electrical circuit to detect the said failure, comprising a U-shaped brittle electrical conducting element having its ends supported in a housing and the U-shaped portion protruding from said housing, electrical leads extending through the wall of said housing and making electrical contact with said ends of said brittle conducting element, means mounting said housing adjacent a rupturable closure member in vessel in a position such that the protruding U-shaped portion of said brittle conducting element is disposed in a place which ensures fracturing of said portion upon rupture of the closure member whereby when said portion fractures into a plurality of fragments, electrical continuity between the electrical leads is broken and the fragments cannot dispose themselves in any way which restores the electrical continuity under the conditions consequent upon the failure.
Claim 2
Dependent Claim
149 words
A detector for the detection of a rupture of a closure member, operable by the breakage of an electrical circuit to detect the said failure, comprising a U-shaped brittle electrical conducting element having its ends supported in a housing and the U-shaped portion protruding from said housing, electrical leads extending through the wall of said housing and making electrical contact with said ends of said brittle conducting element, means mounting said housing adjacent a rupturable closure member in vessel in a position such that the protruding U-shaped portion of said brittle conducting element is disposed in a place which ensures fracturing of said portion upon rupture of the closure member whereby when said portion fractures into a plurality of fragments, electrical continuity between the electrical leads is broken and the fragments cannot dispose themselves in any way which restores the electrical continuity under the conditions consequent upon the failure.
Claim 3
Dependent Claim
22 words
A detector according to claim 1 wherein the electrical conducting element is a layer of metal deposited on a U-shaped glass substrate.
Claim 4
Dependent Claim
17 words
A detector according to claim 2 wherein the glass substrate is in the form of a tube.
Claim 5
Dependent Claim
20 words
A detector according to claim 3 wherein the tube is coated on an internal surface with a layer of metal.
Claim 6
Dependent Claim
24 words
A detector according to claim 1 wherein the electrical conducting element comprises a brittle tubular support having deposited thereon a layer of conducting material.
Claim 7
Dependent Claim
22 words
A detector according to claim 5 wherein the layer of conducting material is deposited on an internal surface of the tubular support.
Claim 8
Dependent Claim
21 words
A detector according to claim 5 wherein the tubular support has a cylindrical form externally over a portion of its length.
Claim 9
Dependent Claim
13 words
A detector according to claim 5 wherein the conducting material is a metal.
Claim 10
Dependent Claim
11 words
A detector according to claim 8 wherein the metal is silver.
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) | 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 |