US3628690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Expansion chamber construction
Assignee: E S RITCHIE AND SONS Inc
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Filing: 1970-02-03
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Granted: 1971-12-21
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Expires: 1990-02-03
Abstract
Abstract An expansion chamber construction for a compass includes an elastic cup-shaped member which surrounds in resting relationship a substantial portion of a split spherical fluid tight chamber structure to define a compact expansion chamber therebetween. The circular rim of the elastic cup-shaped member has integral elastic flange on which is formed an upstanding integral sealing ring. The integral elastic flange and sealing ring are adapted to be compressed in cooperation with flanged portions of the split fluid chamber to seal the chamber. A second sealing ring is preferably integrally formed around a filling hole in the elastic cup to seal the filling hole.
Inventors
- 👤 Allen Butman Sherman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:59
CPC Classifications
G; G01; G01C; G01C17/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
256 words
In a magnetic compass of the type having a spherical fluid filled chamber to dampen movements of a compass card mounted therein, an improved fluid chamber and expansion chamber construction comprising: a hemispherical transparent dome having a radially extending flange at its rim; a mating flanged hemispherical bowl having a radially extending flange at its rim, means defining an aperture in said bowl; and elastic cup-shaped member surrounding said bowl in nesting relationship, said elastic cup-shaped member having a configuration similar to and larger than the outer configuration of said bowl to define a compact expansion chamber therebetween, the inner rim of said elastic cup-shaped member having a circular opening of substantially the same diameter as the outer diameter of said hemispherical bowl, an integral elastic flange extending radially outward from said cup-shaped member circular opening beyond said bowl flange and an upwardly extending elastic sealing ring integrally formed on said elastic flange radially outward from said bowl flange, the uncompressed height of said elastic sealing ring being greater than the height of said bowl flange, whereby said bowl is nested within said elastic cup shaped member to from an elastic cup bowl assembly with said bowl flange resting on said elastic cup-shaped member flange and said integral sealing ring extending above said bowl flange; means for mounting said dome to said cup bowl assembly with said dome flange in opposed relationship to said bowl flange, and means for compressing said sealing ring against said dome flange to seal the junction between said bowl and dome.
Claim 2
Dependent Claim
256 words
In a magnetic compass of the type having a spherical fluid filled chamber to dampen movements of a compass card mounted therein, an improved fluid chamber and expansion chamber construction comprising: a hemispherical transparent dome having a radially extending flange at its rim; a mating flanged hemispherical bowl having a radially extending flange at its rim, means defining an aperture in said bowl; and elastic cup-shaped member surrounding said bowl in nesting relationship, said elastic cup-shaped member having a configuration similar to and larger than the outer configuration of said bowl to define a compact expansion chamber therebetween, the inner rim of said elastic cup-shaped member having a circular opening of substantially the same diameter as the outer diameter of said hemispherical bowl, an integral elastic flange extending radially outward from said cup-shaped member circular opening beyond said bowl flange and an upwardly extending elastic sealing ring integrally formed on said elastic flange radially outward from said bowl flange, the uncompressed height of said elastic sealing ring being greater than the height of said bowl flange, whereby said bowl is nested within said elastic cup shaped member to from an elastic cup bowl assembly with said bowl flange resting on said elastic cup-shaped member flange and said integral sealing ring extending above said bowl flange; means for mounting said dome to said cup bowl assembly with said dome flange in opposed relationship to said bowl flange, and means for compressing said sealing ring against said dome flange to seal the junction between said bowl and dome.
Claim 3
Dependent Claim
36 words
Apparatus of claim 1 in which said compressing means comprises an annular retaining ring underlying said elastic flange opposite to the dome flange and means for drawing said retaining ring in said dome mounting means together.
Claim 4
Dependent Claim
63 words
Apparatus of claim 1 which further includes; means defining a filling hole in said elastic cup-shaped member; a second elastic sealing ring integrally formed around said filling hole; and a removable filler plug having substantially the same diameter as said filling hole, said plug including means for compressing said second elastic sealing ring when inserted in said filling hole to seal the same.
Claim 5
Dependent Claim
15 words
Apparatus of claim 1 in which said dome flange bears directly against said bowl flange.
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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |