Patent US3562531A successfully refreshed from Google Patents.
US3562531A
Expired / Lapsed
US
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Nucleonic measuring apparatus with automatic fire safety radiation source shutter closing and locking means comprising a spring retained by a fusible barrier which melts at high temperatures
Assignee: IND NUCIEONICS CORP
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Filing: 1967-04-27
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Granted: 1971-02-09
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Expires: 1987-04-27
Abstract
Abstract A nucleonic measuring instrument wherein a housing contains a radiation source and has an aperture controlled by a shutter which is spring loaded to a closed position for confining and shielding the radiation and is movable by a motor to an open position for releasing the radiation, the motor being supplied with power through a heat-sensitive element so that it is deenergized and the shutter closes in response to a predetermined high ambient temperature such as may be caused by a fire, and a spring steel shutter lock is retained in a retracted position by a barrier of meltable metal which is adapted to melt and release the spring lock at a still higher ambient temperature for locking the shutter in its closed position.
Inventors
- 👤 George J Trachevski
- 👤 Ernest A Auborn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:38
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/02; G01N23/06; G01N23/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
The instrument of claim 1 wherein said lock means comprises a spring member having a pair or opposite ends which are retained by said barrier means in a stressed condition permitting unrestricted movement of said shutter between its said positions and which are released in response to the removal of said barrier means for movement into said moved position preventing opening movement of said shutter.
Claim 2
Dependent Claim
26 words
The instrument of claim 1 in which said barrier means comprises a eutectic alloy having a predetermined melting point which melts to release said spring member.
Claim 3
Dependent Claim
50 words
The instrument of claim 3 further comprising means in said shutter defining an opening adjacent said shutter guide means, and wherein said lock means comprises a spring wire positioned in saId shutter opening and movable therethrough upon the melting of said material into locking engagement with said shutter guide means.
Claim 4
Dependent Claim
88 words
The instrument of claim 3 wherein said lock means comprises a generally V-shaped spring having opposite end portions, means in said shutter defining a transverse, generally V-shaped recess, said barrier means retaining said spring in said recess in a semifolding stressed condition with the opposite end portions thereof retracted in said opening within the dimensions of said shutter, said end portions being movable upon the said removal of said barrier means outwardly of the transverse dimensions of said shutter and into locking engagement with said shutter guide means.
Claim 5
Dependent Claim
57 words
The instrument of claim 5 further comprising means in said guide means defining openings positioned approximately in alignment with the terminal ends of said recess when said shutter is in its closed position to accept the said opposite end portions of said V-shaped spring with the release of said spring by the melting of said barrier means.
Claim 6
Dependent Claim
165 words
A nucleonic radiation energy measuring instrument having a source of nuclear energy and incorporating a temperature responsive safety lock in which a shutter member is mounted on a guide member for movement between a retracted position defining an opening for radiation measurement purposes and a closed position effectively confining radiation from said source, the improvement in shutter-locking mechanisms comprising means defining a locking spring mounted on one of said shutter and guide members having an integral portion thereof movable between a retracted position permitting movement of said shutter member between its said positions, and an operative position in which said portion is in locking engagement with the other of said shutter and guide members with said portion being normally urged to said operative position, and metal barrier means having a predetermined melting temperature retaining said spring in its said retracted position and flowable upon the attainment of said temperature to release said spring for movement of said integral portion thereof into its said operative position.
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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) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |