US3572775A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brazed fittings
Assignee: McDonnell Douglas Corp
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Filing: 1969-03-10
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Granted: 1971-03-30
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Expires: 1989-03-10
Abstract
Abstract Metal sleeves joined to metal tubing by brazing or welding processes permit the tubing to be removably secured to fittings in piping systems. Similarly, permanent brazed connections between tubing and fittings eliminates a substantial number of potential leak points and a saving in weight is accomplished.
Inventors
- 👤 John C Bloom
- 👤 Frank J Hanback
- 👤 Masashi Hayase
- 👤 Norman F Robinson
- 👤 Wayne S Wheelock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:55
CPC Classifications
F; F16; F16L; F16L13/00; F16L13/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
259 words
In combination a removable brazed fitting comprising a fitting, sleeve, tube and nut: said fitting having external threads to receive said nut, said fitting having a fluid passage bore with a conical opening with an abutting shoulder therebetween; said sleeve having a first bore of the size of said fluid passage bore, a larger bore terminating in a sleeve shoulder communicating with said first bore, a brazing material securing said tube to said sleeve, and said end of said tube abutting said sleeve shoulder; said sleeve having a cylindrical tip end portion adapted to abut said fitting abutting shoulder and an arcuate outer surface adapted to abut said fitting conical opening in fluid-tight fluidtight relationship; said sleeve having a circumferential ring on its outer surface having a conical shoulder thereon; said nut having a bore of sufficient size to permit passage of said nut along said tube and a larger bore for permitting partial passage of said nut over said sleeve circumferential ring, both said bores terminating in a conical shoulder within said nut, said nut conical shoulder abutting said sleeve conical shoulder to exert sealing pressure on said fitting by said sleeve; and said cylindrical tip end portion being of a predetermined length relative to the sealing contact between said arcuate outer surface and said fitting conical opening whereby further insertion of said sleeve into said fitting by tightening of said nut will produce axial loading through said tip into said fitting without significantly increasing the force on said sealing surfaces and damage from overtightening of said nut.
Claim 2
Dependent Claim
259 words
In combination a removable brazed fitting comprising a fitting, sleeve, tube and nut: said fitting having external threads to receive said nut, said fitting having a fluid passage bore with a conical opening with an abutting shoulder therebetween; said sleeve having a first bore of the size of said fluid passage bore, a larger bore terminating in a sleeve shoulder communicating with said first bore, a brazing material securing said tube to said sleeve, and said end of said tube abutting said sleeve shoulder; said sleeve having a cylindrical tip end portion adapted to abut said fitting abutting shoulder and an arcuate outer surface adapted to abut said fitting conical opening in fluid-tight fluidtight relationship; said sleeve having a circumferential ring on its outer surface having a conical shoulder thereon; said nut having a bore of sufficient size to permit passage of said nut along said tube and a larger bore for permitting partial passage of said nut over said sleeve circumferential ring, both said bores terminating in a conical shoulder within said nut, said nut conical shoulder abutting said sleeve conical shoulder to exert sealing pressure on said fitting by said sleeve; and said cylindrical tip end portion being of a predetermined length relative to the sealing contact between said arcuate outer surface and said fitting conical opening whereby further insertion of said sleeve into said fitting by tightening of said nut will produce axial loading through said tip into said fitting without significantly increasing the force on said sealing surfaces and damage from overtightening of said nut.
Claim 3
Dependent Claim
173 words
In combination with a fitting, tube and nut, a sleeve having a bore the size of the fluid passage in said fitting and a counterbore the size of the tube end to be received therein: said sleeve having a circumferential outer ring against which said nut may extent pressure when said nut is tightened on said fitting; said sleeve bore and counterbore forming a tube positioning shoulder in the plane of said sleeve circumferential outer ring; said fitting having an abutting shoulder; said sleeve having an end adapted to abut said shoulder; said fitting bore having a conical surface opening; said fitting abutting shoulder positioned axially inwardly of said conical surface opening; said sleeve having an arcuate outer surfaCe adapted to abut said conical surface; and said nut exerting axial loading pressure sequentially through said circumferential outer ring, through said sleeve end and through said fitting shoulder without significantly increasing the force on the contacting surface between said arcuate outer surface and said conical surface and damage thereto from overtightening of said nut.
Claim 4
Dependent Claim
173 words
In combination with a fitting, tube and nut, a sleeve having a bore the size of the fluid passage in said fitting and a counterbore the size of the tube end to be received therein: said sleeve having a circumferential outer ring against which said nut may extent pressure when said nut is tightened on said fitting; said sleeve bore and counterbore forming a tube positioning shoulder in the plane of said sleeve circumferential outer ring; said fitting having an abutting shoulder; said sleeve having an end adapted to abut said shoulder; said fitting bore having a conical surface opening; said fitting abutting shoulder positioned axially inwardly of said conical surface opening; said sleeve having an arcuate outer surfaCe adapted to abut said conical surface; and said nut exerting axial loading pressure sequentially through said circumferential outer ring, through said sleeve end and through said fitting shoulder without significantly increasing the force on the contacting surface between said arcuate outer surface and said conical surface and damage thereto from overtightening of said nut.
References Cited (Backward Citations)
US1901820A
Cited
US2781785A
Cited
US3069187A
Cited
US3264012A
Cited
US3285627A
Cited
FR1488719A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |