US3850456A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lip seal fittings
Assignee: McDonnell Douglas Corp
•
Filing: 1973-02-28
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Granted: 1974-11-26
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Expires: 1993-02-28
Abstract
Abstract Fittings for establishing sealed connections with bosses, each fitting including a semi-flexible cantilevered sealing lip about the periphery thereof, an undersized threaded portion which aligns and pulls the sealing lip against a chamfered boss surface when the fitting is tightened thereto and a relieved portion between the threaded portion and the lip to enable predetermined stretching and yielding to protect the boss from over-torquing of the fitting and overpressures which may be applied thereto. An optional O-ring and backup ring may be provided under the sealing lip to provide redundant sealing means.
Inventors
- 👤 F Hanback
- 👤 N Robinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:25
CPC Classifications
F; F16; F16L; F16L15/00; F16L15/006; F16L15/008; F16L41/00; F16L41/08; F16L41/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
259 words
A fitting for redundant sealed attachment to a boss comprising: a body portion constructed about an axis; a threaded portion at a first end of said body portion adapted to engage with the boss; a semi-flexible cantilevered lip extending toward said first end portion from said body portion, said lip having a lip tip including a lip tip surface for engagement with the boss to sealably mate therewith, an inner surface having a substantially circumferential portion parallel to the axis of said fitting and a frustroconical portion expanding in diameter from said substantially circumferential portion to adjacent said lip tip, and an outer circumferential surface which slopes inwardly toward said lip tip at an angle of less than 60* to said inner circumferential surface; an O-ring positioned adjacent said lip tip between said lip tip and said body portion to provide a redundant seal for said sealable mating of said lip tip and the boss, said O-ring extending axially forwardly of said lip tip and adapted to sealingly engage the boss; means for maintaining said O-ring positioned adjacent said lip tip; and an elongated thread relief portion adjacent said thread portion and spaced juxtaposed said lip, said thread relief portion being longer than said lip, said body portion further including an inner circumferential surface defining a bore which extends from said first end axially at least partly through said fitting, whereby said inner circumferential surface of said body portion and said thread relief portion thereof define therebetween a weakened portion which can stretch in response to forces applied thereto.
Claim 2
Dependent Claim
259 words
A fitting for redundant sealed attachment to a boss comprising: a body portion constructed about an axis; a threaded portion at a first end of said body portion adapted to engage with the boss; a semi-flexible cantilevered lip extending toward said first end portion from said body portion, said lip having a lip tip including a lip tip surface for engagement with the boss to sealably mate therewith, an inner surface having a substantially circumferential portion parallel to the axis of said fitting and a frustroconical portion expanding in diameter from said substantially circumferential portion to adjacent said lip tip, and an outer circumferential surface which slopes inwardly toward said lip tip at an angle of less than 60* to said inner circumferential surface; an O-ring positioned adjacent said lip tip between said lip tip and said body portion to provide a redundant seal for said sealable mating of said lip tip and the boss, said O-ring extending axially forwardly of said lip tip and adapted to sealingly engage the boss; means for maintaining said O-ring positioned adjacent said lip tip; and an elongated thread relief portion adjacent said thread portion and spaced juxtaposed said lip, said thread relief portion being longer than said lip, said body portion further including an inner circumferential surface defining a bore which extends from said first end axially at least partly through said fitting, whereby said inner circumferential surface of said body portion and said thread relief portion thereof define therebetween a weakened portion which can stretch in response to forces applied thereto.
Claim 3
Dependent Claim
69 words
The fitting defined in claim 1 wherein said elongated thread relief portion includes first and second cylindrical surfaces, said first cylindrical surface having a diameter which is less than the diameter of said second surface, said first cylindrical surface being closer to said first end of said body than said second cylindrical surface, said second cylindrical surface being juxtaposed said lip to urge said O-ring toward said lip tip.
Claim 4
Dependent Claim
31 words
The fitting defined in claim 2 wherein said means for maintaining said O-ring positioned adjacent said lip tip includes: a ring which nests between said lip and said thread relief portion.
Claim 5
Dependent Claim
24 words
The fitting defined in claim 3 wherein said ring is constructed from material which permanently deforms with time and pressure into any voids thereabout.
Claim 6
Dependent Claim
58 words
The fitting defined in claim 4 wherein said lip tip includes: a generally semi-toroid end surface, said end surface being defined by revolving a portion of a circle in a plane perpendicular to said fitting axis, said circle being revolved having a radius at least about half as long as said lip so said lip tip is robust.
Claim 7
Dependent Claim
25 words
The fitting defined in claim 5 wherein the center of said revolved circle defining a locus is positioned between said lip and said relief portion.
Claim 8
Dependent Claim
26 words
The fitting defined in claim 6 including means on said body portion for applying predetermined torque to said fitting for installing said fitting in a boss.
References Cited (Backward Citations)
US2889733A
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US3145035A
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US3101206A
Cited
US3151896A
Cited
US3376053A
Cited
US3730563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |